• Korean Journal of Poultry Science
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• v.30 no.4
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• pp.269-273
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• 2003

A cecostomy technique (surgery for inserted tube into ceca) was developed to quantify urine backflow into the ceca of fed and feed-deprived chickens. Two days post-surgery, cecostomised chickens were flushed with 20ml of warm saline solution every other day for 10 days. Excreta were collected daily from cecal tubing and cloaca by surgical attachment of polyethylene collection vessels to the chickens. Uric acid excretion was significantly increased in fed compared to feed-deprived chickens (P<0.05). Amount of determined uric acid from the ceca was 7.74% and 5.31% of total excretion for fed and ffeed-deprived chickens, respectively. Post-mortem examinations ascertained that the caeca were intact around the Latex tubing. The results of the study indicated that at least 5% of daily urine production flow retrograde into the ceca of roosters.

• Journal of Korean Society of Steel Construction
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• v.10 no.2 s.35
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• pp.303-315
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• 1998

Four types of repair procedures are applied to the fatigue cracked crane runway gilders, which are stop-holes as crack arrester stop-holes reinforced with high strength bolts, welding repair and reinforcement with high strength bolted splices. The fatgiue cracks are reinitiated at the region where stop-holes and weld repairments are applied, while none of the cracks are observed in the cases of stop-holes reinforcement and reinforcement with high strength bolted splices. When using stop-holes and hole-reinforcement all repaired regions show a same fatigue strength to the one before the repairments. The experiments also reveal that the proper weldment is an essential factor when applying the welding repairement as a properly welding produces the same level of fatigue strength after the repairement. When the situation permits to use reinforcement with high strength boilted splices, the experiments shows the repairment is the best possible method among the procedures available.

• Journal of Korean Society of Transportation
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• v.35 no.5
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• pp.447-457
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• 2017

This study aims to analyze the accidents of green mode bicycle. In pursuing the above, this study gave special emphasis on modeling the bicycle accidents reflecting the regional characteristics. The main results are as follows. First, the null hypotheses that the number of accident and ratio of serious injury and fatality (FSI) were the same over regions were rejected. Second, as the common variables, the number of bicycle was judged to have positive (+) impact to the accidents and the bicycle using ratio was inferred to increase the ratio of FSI. Third, the elderly population ratio among 3 factors which gave impact to the accidents of Si_A (city-county consolidation) was concluded to have the greatest elasticity. The developed area ratio between 2 factors in Si_B (city which is not consolidated) was, however, estimated to have the higher elasticity. Fourth, the number of car registration among 5 accident factors of Gun (county) was analyzed to have the greatest elasticity. Finally, the commuting trip ratio among 7 accident factors of Gu (district) was judged to have the greatest elasticity. This study can be expected to give some implications to regional policy-making related to bicycle.

• Korean Journal of Veterinary Service
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• v.39 no.2
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• pp.87-92
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• 2016

Porcine edema disease (ED) is a communicable disease of pigs caused by infection with Shiga toxin (Stx)-producing Escherichia coli (STEC) which expresses F18 fimbriae and/or Stx type 2e (Stx2e). While STEC causes a severe illness including hemorrhagic colitis and hemolytic-uremic syndrome in humans, it induces damage to the vascular endothelium, which results in edema, hemorrhage, and microthrombosis, leading in high mortality in pigs. In the present study, we cultured Stx2e-producing E. coli field isolates from conventional pig farms that experienced sudden deaths previously with symptoms similar to porcine edema disease, which were further investigated with Shiga toxin profiles. A total of 43 strains were identified from the collected samples by F18 or Stx2e specific PCR. Based on the PCR, 42 isolates out of 43 isolates were proved to carry one of F18 or Stx2e genes and 14 isolates to carry both F18 and Stx2e genes. All of the 30 isolates that harbored Stx2e gene induced the cytopathic effect (CPE) in vero cells and especially, the isolate 150229 produced the highest level of Shiga toxin. Therefore, we identified the virulence genes (F18 and Stx2e) and demonstrated Shiga toxin-producing abilities from porcine edema disease causing E. coli filed isolates. These results suggested that one of the isolates could be a vaccine antigen candidate against STEC through further investigating to elicit an immune response.

• 한국해양학회지
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• v.13 no.2
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• pp.11-16
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• 1978

The contents of heavy metals were studied on sediments collected from the southeastern coastal area of Korea.Concentrations of the elements showed Cu 14∼ 48ppm (av. 18ppm), Pb 14∼49ppm (av. 28ppm), Zn 79∼187ppm (av. 11ppm), Co 11∼ 15ppm (av. 13ppm), Ni 22∼32ppm (av. 29ppm), Fe 3.1∼5.3% (av. 4.3%) and Mn 333 ∼1010ppm (av. 499ppm). When these values are compared with those of the unpolluted near-shore sediments from other countries,there seems to be little environmental contamination of heavy metals in the sediments of the study area. However, from the fact that the nearer to harbor the stations are, the higher the contents of copper, lead and zinc are in the sea off Pusan Bay, it is suggested that heavy metals in the sediments are starting to show some contamination from man's activities.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.167-174
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• 2018

This study attempts to construct a model of optimal headway, focusing on a practical applicability to bus transit operation. Examining the existing bus operation and scheduling plans imposed by Busan City, we found that the plans failed to reasonably take into account such realities as varying traffic and operational conditions. The model is thus developed to derive the hourly optimal headway by routes satisfying the real-world conditions: varying hourly demand and cycle time, applying the model to routes 10 and 27 as examples. To do so, we collect big-dataset generated by smart card system and BIMS (Bus Inforamtion Management System). It is expected that the results of this study wil be a basis for further refined research in this field as well as for preparing practical timetables for bus operation.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.3
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• pp.127-136
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• 2011

The typical unit infrastructure cost estimation techniques adopted so far in implementing the Korean Impact Fee Zoning have rather been centered around the unilateral simple cost models. The techniques, as such, have frequently been criticized for their lack of flexibility in properly reflecting the regional differences as well as the peculiarities of individual development projects. The Ministry of Land, Transport, and Maritime Affairs (MLTM), in this regard, has recently introduced an enhanced alternative technique. Using the NGIS data, the study probes the viability of the MLTM's new technique by testing the entire estimation process based on the case area in Ansung City. Reflecting the City's characteristics, the study assumes a composite land use plan that accommodates the industrial area in addition to typical residential areas. As an extensive empirical case study, the research has found from the new technique considerable technical merits to overcome the existing shortcomings and summarized its significant policy implications.

• Journal of Surface Science and Engineering
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• v.42 no.3
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• pp.116-121
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• 2009

The 2-step low temperature plasma processes (the combined carburizing and post-nitriding) offer the increase of both surface hardness and thickness of hardened layer and corrosion resistance than the individually processed low temperature nitriding and low temperature carburizing techniques. The 2-step low temperature plasma processes were carried out for improving both the surface hardness and corrosion resistance of AISI 316L stainless steel. The influence of gas compositions on the surface properties during nitriding step were investigated. The expanded austenite (${\gamma}_N$) was formed on all of the treated surface. The thickness of ${\gamma}_N$ and concentration of N on the surface increased with increasing both nitrogen gas and Ar gas levels in the atmosphere. The thickness of ${\gamma}_N$ increased up to about $20{\mu}m$ and the thickness of entire hardened layer was determined to be about $40{\mu}m$. The surface hardness was independent of nitrogen and Ar gas contents and reached up to about 1200 $HV_{0.1}$ which is about 5 times higher than that of untreated sample (250 $HV_{0.1}$). The corrosion resistance in 2-step low temperature plasma processed austenitic stainless steels was also much enhanced than that in the untreated austenitic stainless steels due to a high concentration of N on the surface.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.41-48
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• 2009

This study investigated the characteristics of spatial expansion/centralization and the spatial structural change of urban. The data used in analysis were urban population, employment, building floor area, and land price. The analysis was performed for the data of 1995, 2000, and 2005 during 10 years after 1995. The method of research was as follows; The movement of mean center and standard distance/standard deviation ellipse was estimated to investigate the urban growth change. The result of Moran's I analysis showed a clustered pattern, not a dispersed pattern, however; the effect was not significant. The town area requires the well-ordered urban planning such as land use. The contours map demonstrates that a monopole structure was generally transformed into a multicentralization structure. The development of mutural connection axis among central street roads was fragile.

• Journal of the Korean Geographical Society
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• v.44 no.4
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• pp.429-446
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• 2009

To understand the sulfur flux and cycle in the forest catchment, the hydrological processes and chemical variation of soil solution, groundwater and stream water were analyzed at the Matsuzawa catchment located in the Kiryu Experimental Basin, Shiga Prefecture, central Japan. Unsaturated soil layer at the upper slope of catchment was the source area of ${SO_4}^{2-}$, and deep soil layer and groundwater were the sink zone of ${SO_4}^{2-}$. The vertical distribution of ${SO_4}^{2-}$ concentrations in groundwater affected seasonal variation of ${SO_4}^{2-}$ concentrations in stream water, as groundwater level changed. It is reasonable to assume that each hydrological processes in the forest catchment play an important roles in the retention and discharge of ${SO_4}^{2-}$.