• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.6
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• pp.1872-1881
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• 1996

LBB(Leak-Before-Break) analysis is performed for the highest stress location of each different type of mateerials in the nuclear piping line. In most cases, the highest stress occurs in the pipe and nozzle interface location. i.e. terminal end. The current finite element analysis approach utilizes the symmetry condition both for locations near the nozzle and for locationa away from the nozzle to minimize the size of the finite element model and to make analysis simple when calculating the J-integral values at the crack tip. In other words, the nozzle is not included in the finite element model. However, in reality, the symmetric condition is not applicable for the pipe-nozzle interface location. Because the pipe-nozzle interface location is asymmetric due to different stiffenss of the pipe and nozzle(both material and dimensions). The simplified analysis approach for pipe-nozzle interface locaiton is too conservative for a smaller diameter piping. In tlhis paper, various analyses are performed for the range of materials and crack sizes to evaluate the nozzle effect for a LBB anlaysis. This paper presents methodology for developing the piping evaluaiton diagram at the pipe-nozzle interface location.

• Microbiology and Biotechnology Letters
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• v.46 no.3
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• pp.288-299
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• 2018

Food bio preservation is of major interest in the food industry. Many types of antimicrobial compounds can be produced by lactic acid bacteria (LAB), including bacteriocins. Bacteriocins increase the shelf-life of food by decreasing some food-borne diseases. In this study, a multi-coding sequence of bacteriocin genes was used for primer design to produce bacteriocin genes in Enterococcus faecium AH2 strain and Pediococcus pentosaceus AH1. Multi-coding sequences were aligned to detect conserved sequences in the bacteriocin gene. Eight genes encoding proteins involved in bacteriocin production were isolated and sequenced, including six from E. faecium AH2 (entA, entI, entF, entR, orfA2, orfA3) and two from P. pentoceseus AH1 (papA, pedB), and all gene sequences were deposited in the Gen Bank database under accession numbers LC064146-LC064151, LC101300, and LC101789, respectively. P. pentosaceus AH1 and E. faecium AH2 strains displayed bacteriocin activities of $2610AU\;mL^{-1}$ and $690AU\;mL^{-1}$ and inhibition zones of 26 mm and 19 mm, respectively. Overexpression of entA in E. faecium AH2 increased the bacteriocin and antimicrobial activities.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.4
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• pp.12-19
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• 2014

A signal plan focused on vehicle traffic could easily overlook vulnerable priority signals, although the importance of vulnerable movements is increasingly recognized in recent years. Especially, the vulnerable are sometimes faced with dangerous situations when crossing roads with a signal plan based on design values of average, non-vulnerable persons. This study is focused on how to minimize the vehicle delay while simultaneously considering traffic flow and providing traffic safety by increasing road crossing time for pedestrians. For this purpose, a priority signal control strategy for the vulnerable, considering vehicle traffic flow, has been tested. Practical implication and a microscopic computer simulation has shown that the proposed method could provide a small decrease (about 6.2%) in pedestrian delay, a small increase (about 8.5~13.3%) in travel speed of passing traffic, and a considerable decrease (16.2~26.9%) in vehicle travel time. These findings suggest that the proposed signal control strategy could increase pedestrian safety and diminish delay of vehicle travel.