• 대한안전경영과학회지
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• 제2권4호
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• pp.1-8
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• 2000

Equipment and machine of industrial plant are give effect to mechanical-stress of many working-stop or long time operating. Therefore, to be old and decrepit of every king of equipment. As long time operating equipment period into increase conservation and of repair equipment time is efficacious necessity of utility factor gradually that of productivity of diminution and complete equipment expense of increase. Conservation at special skill working and necessity is that will effectually and complete a period prevention management diagnosis can conservation point at issues at in advance.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2000년도 추계학술발표논문집
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• pp.181-185
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• 2000

• 산업공학
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• 제21권4호
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• pp.411-417
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• 2008

An impeller is a type of high-speed rotor that is used to compress or transfer fluid under high-speed and pressure at high temperatures. The impeller is composed of an axial hub and several blades attached along the hub. The weight and shape of an impeller must be balanced, because their imbalances can cause noise and vibration, which can lead to the breakage of the impeller blades during operation. Thus, the hub and blades of an impeller are commonly machined in a 5-axis NC machine to obtain qualified surfaces. The impeller machining strategy or process plan can not be easily obtained due to the complex, overlapped and twisted shapes of impeller blades. Skillful machining process planners may generate appropriate machining strategies based on their experiences and floor data. However, in practice most shop floor data for the impeller machining is not well-structured such that it does not effectively provide a process planner with information for machining strategies and/or process plans. This paper reports the development of a case-based machining strategy support system (CBMS) that employs case-based reasoning to obtain the machining strategy of an impeller by using the existing machining strategies of the shop floor. The CBMS generates impeller machining strategies through a stepwise reasoning process considering the similarity features between the blade shapes and machining regions. A case study is provided to demonstrate that CBMS can generate useful machining strategies facilitating process planners. The developed system can simulate the tool paths of impeller machining and runs on the web.

• Journal of Microbiology and Biotechnology
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• 제19권3호
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• pp.277-285
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• 2009

The nucleotide sequence of the Paenibacillus curdlanolyticus B-6 xyn10A gene, encoding a xylanase Xyn10A, consists of 3,828 nucleotides encoding a protein of 1,276 amino acids with a predicted molecular mass of 142,726 Da. Sequence analysis indicated that Xyn10A is a multidomain enzyme comprising nine domains in the following order: three family 22 carbohydrate-binding modules (CBMs), a family 10 catalytic domain of glycosyl hydrolases (xylanase), a family 9 CBM, a glycine-rich region, and three surface layer homology (SLH) domains. Xyn10A was purified from a recombinant Escherichia coli by a single step of affinity purification on cellulose. It could effectively hydrolyze agricultural wastes and pure insoluble xylans, especially low substituted insoluble xylan. The hydrolysis products were a series of short-chain xylooligosaccharides, indicating that the purified enzyme was an endo-$\beta$-1,4-xylanase. Xyn10A bound to various insoluble polysaccharides including Avicel, $\alpha$-cellulose, insoluble birchwood and oat spelt xylans, chitin, and starches, and the cell wall fragments of P. curdlanolyticus B-6, indicating that both the CBM and the SLH domains are fully functioning in the Xyn10A. Removal of the CBMs from Xyn10A strongly reduced the ability of plant cell wall hydrolysis. These results suggested that the CBMs of Xyn10A play an important role in the hydrolysis of plant cell walls.

• 한국산학기술학회논문지
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• 제22권1호
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• pp.575-584
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• 2021

본 연구는 연속행동모니터링시스템(CBMS)을 사용하여 저온 충격에 노출된 참돔 Pagrus major 치어의 행동반응에 대한 임계 수온 및 행동 내성 반응을 규명하였다. 실험생물의 행동은 8.0~20.0℃ 수온구간에서 12시간과 24시간 마다 각각 2.0℃와 4.0℃씩 하강시키며 관찰하였다. 참돔 치어는 12.0℃ 이하로 수온이 하강한 경우 수온 노출시간과 변동 폭에 관계없이 유영활동이 감소하고 정지가 반복되는 불안정한 행동패턴이 관찰되었다. 또한 8.0~10.0℃ 수온에 노출된 생물의 유영능력은 급격히 저하되어 수조 바닥에서 머무르는 아치사 반응 행동을 보였다. 실험어류는 저 수온 스트레스 영향을 받아 생물의 50 %만 생존하였으며, 저온 충격(cold shock) 후 6시간 이내에 모든 개체가 사망하였다. 또한 행동지수(BI)는 급격히 감소하였으며 변이계수(CV)의 진폭변화는 타 수온보다 변동 폭이 큰 것으로 분석되었다(p<0.05). 참돔 치어의 저온 스트레스는 12.0℃를 경계로 촉진되며, 8.0~10.0℃의 저온 충격에 노출된 생물의 아치사 반응을 유발시키는 내성한계인 것으로 해석된다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.51-51
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• 2017

• Advances in concrete construction
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• 제11권5호
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• pp.419-428
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• 2021

The pH of cement-based materials (CBMs) is an important factor for their durability, sustainability, and long service life. Currently, the use of supplementary cementitious materials (SCMs) is becoming mandatory due to economic, environmental, and sustainable issues. There is a decreasing trend in pH of CBMs due to incorporation of SCMs. The determination of numerical values of pH is very important for various low and high volume SCMs blended cement mortars for the better understanding of different defects and durability issues during their service life. In addition, the effect of cement hydration and pozzolanic reaction of SCMs on the pH should be determined at initial and later ages. In this study, the effect of low and high-volume fly ash (FA) and ground granulated ballast furnace slag (GGBFS) cement mortars in different curing conditions on their pH values has been determined. Thermal gravimetric analysis (TGA) was carried out to support the findings from pH measurements. In addition, thermal conductivity (k-value) and strength activity indices of these cement mortars were discussed. The results showed that pH values of all blended cement mortars were less than ordinary Portland cement (OPC) mortar in all curing conditions used. There was a decreasing tendency in pH of all mortars with passage of time. In addition, the pH of cement mortars was not only dependent on the quantity of Ca(OH)₂. The effect of adding SCMs on the pH value of cement mortar should be monitored and measured for both short and long terms.

• Advances in concrete construction
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• 제15권3호
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• pp.191-202
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• 2023

Palm oil fuel ash (POFA) is a newly emerging pozzolanic material having high amount of silica content. Various forms of POFA were used in cement-based materials (CBMs) in replacement of cement in different dosages of low and high volume. Although, there are many researches on POFA to be used in concrete and mortar, however, this material was not practically used in the construction industry. Engineers and designers need to be confident to use any new developed materials by knowing all engineering properties at short and long terms. As durability concern, concrete pH value is one of the most important properties. Portland cement produces are alkaline initially, however, it may be reduced due to aging and its components. It is believed that by incorporation of supplementary cementitious materials in CBMs the pH value reduces due to utilization of Ca(OH)₂ in pozzolanic reaction. This study is the first attempts to understand the pH value of mortars containing up to 30% POFA under different curing conditions and its changes with time. The results were also compared with the pH of ground granulated ballast furnace slag (GGBFS) and fly ash (FA) content mortars. In addition, the compressive strength of different mortars under different curing conditions were also studied. The results showed that the pH value of control mix (without cementitious materials) was more than all the blended cement mortars indifferent curing conditions at the same ages. However, there was a reducing trend in the pH value of all mortar mixes containing POFA.

• Bulletin of the Korean Chemical Society
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• 제35권3호
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• pp.933-937
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• 2014

A derivative of Mycobacterium bovis Bacillus Calmette-Guerin (BCG) has been used for the preparation of tuberculosis vaccines. To establish a Korean tuberculosis vaccine derived from BCG-Pasteur $1173P_2$, genome sequencing of a BCG-Korea strain was completed by Joung and coworkers. A comparison analysis of the genome sequences of the BCG-Pasteur $1173P_2$ and BCG-Korea strains showed marginal increases in the total genome length (~0.05%) and the number of genes (~4%) in the BCG-Korea genome. However, how the genomic changes affect the BCG-Korea protein expression levels remains unknown. Here, we provide evidence of the proteomic alterations in the BCG-Korea strain by using a SWATH-based mass spectrometric approach (Sequential Window Acquisition of all THeoretical mass spectra). Twenty BCG proteins were selected by top-rank identification in the BCG proteome analysis and the proteins were quantified by the SWATH method. Thirteen of 20 proteins showing significant changes were enough to discriminate between the two BCG proteomes. The SWATH method is very straightforward and provides a promising approach owing to its strong reliability and reproducibility during the proteomic analysis.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.3071-3076
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• 2014

Proteomic analyses of the excretory/secretory proteins from the RH strain of Toxoplasma gondii have been performed to understand their functions in the host-parasite interaction. A total of 34 proteins were identified from LC/MS/MS analysis and their abundance was estimated by spectral counting methods. Among them, 8 species of micronemal proteins (MICs), 2 species of rhoptry proteins (ROPs), and 6 species of dense granular proteins (GRAs) were confirmed. Besides these, 18 species of protein were newly identified, and their cellular functions were estimated from sequence analysis. The three most abundant of the 34 identified extractor/secretory proteins-GRA1, GRA7 and GRA2-were confirmed to be highly expressed in T. gondii using the spectral count method. This phenomenon is another demonstration of the importance of GRA proteins for the penetration and survival of T. gondii.