• 대한수의학회지
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• 제39권4호
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• pp.743-750
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• 1999

Bovine viral diarrhea viruses (BVDVs) were isolated from cattle with respiratory and diarrhea signs as well as persistently infected cattle. These isolates were analysed serologically to characterize serogroups and to compare serological relationship with reference viruses of type I and II. Most isolates from calf diarrheal cases and persistently infected individuals showed a significant difference in cross-neutralization test with the viruses isolated from nasal discharges showing severe respiratory signs. Serologically most of the commercial vaccine strains could be classified into classical BVDV (type I) such as NADL strain. This serological difference among BVDV isolates suggested the need for new vaccines to protect cattle from both respiratory and enteric BVDV infections in field. The immunogenicity of BVDVs which showed a good propagation capability in MDBK cells and high rates of neutralizing activity (isolate : KD26-1, PHG, B5 and 95002) against all viruses used in this study, was confirmed in guinea pig when treated as single or combined groups.

• Journal of Microbiology
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• 제34권2호
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• pp.124-130
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• 1996

A survey was conducted to determine the prevalance of infectious pancreatic necrosis virus (IPNV) on fish farms in Korea and the epidemiology of IPNV infection in the farmed rainbow trout. In total, 43 pools of rainbow trout with apparent signs of viral infection from five provinces were obtained and analyzed. Evident cytopathic effects, including karyopycnosis and cell destruction, were observed in CHSE (chinook samlmon embyro)-214 cells infected with the virus isolates. Of these, ten viral isolates were assumed to be IPNV based on biophysical properties. RNA analysis revealed that the isolates contained two-segmented RNA genomes, further indicating that the viral isolates are IPNV. Antigenic comparison of the IPNV isolates identified three distinct serological groups separable by the cross-neutralization test. Of the ten IPNV isolates, six could be classified as strain DRT, two as strain Ab, and two as strain VR299. We were not able to isolate new strain of IPNV or any isolate serologically similar to the standard strain Sp.poraceae and families of the Agaricales, they are genetically more related to the Polyporaceae. These results are consistent with morphological characters observed in those mushrooms. However, it is premature to conclude taxonomic status Ganoderma species in the present study employing small sample size.

• Macromolecular Research
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• 제16권8호
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• pp.734-740
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• 2008

A new crosslinked, poly(acrylic acid)-based, dehydrating agent was synthesized through solution polymerization. The Taguchi method, a robust experimental design, was adopted to optimize the synthetic conditions based on the moisture and water absorbing capacities of the dehydrating agent. The method applied for the experiment was a standard L27 ($3^8$) orthogonal array with eight parameters and three levels. By analyzing the variance of the test results, the most effective parameters to control the moisture absorbing capacity (MAC) and its rate were the kind of alkaline base (LiOH, NaOH, or KOH) used as a neutralizing agent of the acrylic acid monomer and the degree of neutralization: The maximum MAC of 40% was achieved at only 2 hat $32^{\circ}C$ and 50% RH when KOH was used as a base and the degree of neutralization was 90%, respectively. However, the water absorbing capacity (WAC) of the resulting dehydrating agent was very low at 158 g/g, indicating that WAC is unaffected by MAC and its rate in this system. The surface morphologies of the agents were examined using scanning electron microscopy (SEM).

• 한국안전학회지
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• 제19권2호
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• pp.98-103
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• 2004

Shotcrete needs the enough durability without deterioration for life time. But shotcrete is being deteriorated according to aging like concrete by internal causes whithin itself and by external causes which can be physical, chemical, or mechanical. Durable shotcrete can be made by incresing the cement content, adding chemical and mineral admixtures and so on. So, in this study, chloride ion penetration test, freeze and thaw test, neutralization test were conducted to examine the durability characteristice of shotcrete with mineral admixtures such as silica fume, blast-furnace slag and fly ash. These results indicate that shotcrete with silica fume is durable. Therefore, the present study provides a firm base to make high performance shtcrete.

• 한국동물위생학회지
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• 제24권3호
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• pp.271-278
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• 2001

Swine sera collected from January to December 2000 were tested for the survey on transmissible gastroenteritis(TGE) infection in Gyeongbuk province. Serum neutralization(SN) test was peformed in finishing pigs of 50 pigs industry without clinical signs of TGE and sows, gilts and growing pigs of four pigs industry with TGE. As the results of SN test in fifty industry, antibody titers of 90.6%(474/523 samples) showed below 4. Antibody titers of them showed highly in two pigs industry of western region and three pigs industry of southern region of Gyeongbuk province. The results indicated that TGE had been occurred before in five pigs industry. Most of antibody titers showed of highly in four pigs industry having had TGE. There were no significant differences of the antibody titers of TGE according to age when the survey was made. The above results indicated that the pigs of Gyeongbuk province were not almost exposed in porcine respiratory coronavirus(PRCV) by present.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.629-632
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• 2006

This study investigated the engineering properties of crushed sand, based on improvement quality technology, and washed sand concrete by conducting mock-up test, in order to verify the availability of crushed sand for full sized structure. Test results showed that fluidity, air content, supersonic waves and corrosion state of concrete using crushed sand had favorable results. In addition, it is found that compressive strength, drying shrinkage length change, hydration heat and neutralization of crushed sand concrete exhibited similar tendency, with that of washed sand concrete. The crushed concrete using developed quality improvement technology shows comparable performance to washed sand concrete.

• 대한수의학회지
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• 제38권3호
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• pp.581-588
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• 1998

Eight monoclonal antibodies(MAbs) against bovine coronavirus(BCV) were produced and characterized. Three MAbs(1G9, 4H12, 5C1) specific to the S glycoprotein and two HE glycoprotein-specific MAbs(2A5, 5G4) were found to neutralize the BCV in fluorescence focus neutralization(FFN) test. Two HE-specific MAbs from the neutralizing MAbs inhibited the hemagglutinating activity of the BCV. None of the N protein-specific MAbs(1C1, 5A12, 6H1) neutralized the virus infectivity. Bovine coronavirus and mouse hepatitis virus, which belong to group II coronaviruses, were differentiated from other groups of coronaviruses(porcine transmissible gastroenteritis virus, porcine epidemic diarrhea virus, canine coronavirus) by all MAbs in fluorescence antibody test(FA), but not in FFN test.

• 한국안전학회지
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• 제18권3호
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• pp.109-113
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• 2003

Concrete and shotcrete should withstand the conditions for which they have been designed, without deterioration, over a period of years. But connote and shotcrete are being deteriorated according to aging by internal and external causes. Recently, many studies on the durability of concrete have been conducted But the durability of shotcrete is rarely studied. So, in this study, chloride ion penetration test freeze and thaw test neutralization test were conducted to examine the durability characteristics of shotcrete with several accelerator and chemical admixture types. These results indicate that shotcrete with allah free accelerator and with superplasticizer are durable. Therefore, the present study provides a fm base to make high performance shotcrete.

• 대한수의학회지
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• 제48권1호
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• pp.83-88
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• 2008

In total, 1,142 serum samples were collected from 223 goat flocks rising in five different regions of Korea. These samples were screened for the presence of border disease virus (BDV) antibodies using an enzyme linked immunosorbent assay. Of the 1,142 samples, we found 47 bovine viral diarrhea virus (BVDV) positive cases (4.1%). These positive serum samples were also examined further by using the virus neutralization test against BDV. In addition, samples were tested for both BVDV and classical swine fever virus (CSFV). All of the samples that were seropositive for BDV also demonstrated positive antibody titers against BVDV and CSFV. Due to their common antigenicity, we also determined further the prevalence and carried out virus neutralization test against three pestiviruses: 314 of the goat samples were screened using reverse transcription polymerase chain reaction with primer pairs specific to common pestivirus genome regions. Overall, 1.6% (5/314) of the samples tested was positive for pestivirus. Based on the nucleotide sequence data and the phylogenetic analysis, three isolates were characterized as BVDV type 1 and two isolates as BVDV type 2. However, none of the isolates could be classified as BDV. These results indicate that BVDV-1 and BVDV-2 are the pestivirus strains circulating among Korean goat populations.

• Computers and Concrete
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• 제6권4호
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• pp.269-280
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• 2009

In this paper an experimental study of the influence of hot springs curing upon concrete properties was carried out. The primary variables of the investigation include water-to-binder ratio (W/B), pozzolanic material content and curing condition. Three types of hot springs, in the range $40-90^{\circ}C$, derived from different regions in Taiwan were adopted for laboratory testing of concrete curing. In addition, to compare with the laboratory results, compressive strength and durability of practical concrete were conducted in a tunnel construction site. The experimental results indicate that when concrete comprising pozzolanic materials was cured by a hot spring with high temperature, its compressive strength increased rapidly in the early ages due to high temperature and chloride ions. In the later ages, the trend of strength development decreased obviously and the strength was even lower than that of the standard cured one. The results of durability test show that concrete containing 30-40% Portland cement replacement by pozzolanic materials and with W/B lower than 0.5 was cured in a hot spring environment, then it had sufficient durability to prevent steel corrosion. Similar to the laboratory results, the cast-inplace concrete in a hot spring had a compressive strength growing rapidly at the earlier age and slowly at the later age. The results of electric resistance and permeability tests also show that concrete in a hot spring had higher durability than those cured in air. In addition, there was no neutralization reaction being observed after the 360-day neutralization test. This study demonstrates that the concrete with enough compressive strength and durability is suitable for the cast-in-place structure being used in hot spring areas.