• Journal of the Korean Society for Precision Engineering
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• v.15 no.8
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• pp.17-25
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• 1998

Aluminum alloys have low density, relatively high strength and yield strength, good plasticity, good machinability, and high corrosion and acid resistance. Therefore, they are suitable for large containers for the food, chemical and other industries. Large containers are often bodies of revolution consisting of shell courses, stiffening rings, heads and other elements joined by annular welds. Larger containers have longer welds and require greater leak-tightness and higher weld mechanical properties. The LNG tank consists of aluminum plates with various sizes, so its construction should by divided by several sections. Moreover, each section has its own sub-section consisted of several aluminum plates. To guarantee the quality of huge LNG tank, therefore, the precise control of plate dimension should by urgently needed in conjunction with the appropriate selection of process parameters such as cutting speed, depth of cut, rotational speed and so on. In this paper, a manufacturing system was developed to implement automatic circular tracking in height direction and automatic circular interpolation in depth of cut direction. Also, the neural network based on the backpropagation algorithm was used to predict the cutting quality and motor load related with the life time of the developed system. It was revealed that the manufacturing system and the neural network could be effectively applied to the bevelling process and to predict the quality of machined area and the motor load.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.108-114
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• 2015

Curvularia lunata is an important maize foliar fungal pathogen that distributes widely in maize growing area in China, and several key pathogenic factors have been isolated. An yeast two-hybrid (Y2H) library is a very useful platform to further unravel novel pathogenic factors in C. lunata. To construct a high-quality full length-expression cDNA library from the C. lunata for application to pathogenesis-related protein-protein interaction screening, total RNA was extracted. The SMART (Switching Mechanism At 5' end of the RNA Transcript) technique was used for cDNA synthesis. Double-stranded cDNA was ligated into the pGADT7-Rec vector with Herring Testes Carrier DNA using homologous recombination method. The ligation mixture was transformed into competent yeast AH109 cells to construct the primary cDNA library. Eventually, a high qualitative library was successfully established according to an evaluation on quality. The transformation efficiency was about $6.39{\times}10^5$ transformants/$3{\mu}g$ pGADT7-Rec. The titer of the primary cDNA library was $2.5{\times}10^8cfu/mL$. The numbers for the cDNA library was $2.46{\times}10^5$. Randomly picked clones show that the recombination rate was 88.24%. Gel electrophoresis results indicated that the fragments ranged from 0.4 kb to 3.0 kb. Melanin synthesis protein Brn1 (1,3,8-hydroxynaphthalene reductase) was used as a "bait" to test the sufficiency of the Y2H library. As a result, a cDNA clone encoding VelB protein that was known to be involved in the regulation of diverse cellular processes, including control of secondary metabolism containing melanin and toxin production in many filamentous fungi was identified. Further study on the exact role of the VelB gene is underway.

• Fire Science and Engineering
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• v.25 no.4
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• pp.1-7
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• 2011

Recently the interest in disaster prevention on super tall buildings is increasing. Especially in fire, against increasing of evacuation time due to high-rise, It is being tried to minimize the fire spread in building. Fire compartments using the fire-resistant wall and door, typical method to control the fire spread in buildings, delay the fire spread to other compartments and consequently evacuation time increases. But the existing provisions adjure only 2-hour fire resistance with maximum limit regardless of the super tall buildings, so this is a obstacle for research and development of the fire resistance wall in super tall buildings. In this study, we reviewed the fire resistance ratings of the wall, and presented the development directions for the fire resistance wall in super tall buildings considering fire resistance, construction and application of the wall.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.127-136
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• 2007

With the construction of vast networks, Internet based services such as online games and Internet banking are steadily increasing. As dysfunctions of the trend, various threats from worms/viruses to hacking are proliferating and new types and variations of worms/viruses are emerging. In response to the problems, telecommunication carriers and the government we establishing systems to cope with infringement accidents and resultant damages. However, in case of nationwide emergencies like the 1.25 Accident, infringement may spread rapidly while analyzing what kind of infringement it is and that may result in enormous losses. Thus, the paper purposed to analyze the states of infringement accidents occurring at each network and coping methods and checklist, based on the results. and to propose strategies for controlling services in case of large scale infringement accidents.

• Tunnel and Underground Space
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• v.16 no.5 s.64
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• pp.387-393
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• 2006

This paper introduces the combination of two blasting methods applied to reduce blast-vibration and increase blast efficiency. NDC (New Deck Charge) blasting method using air deck effect with separation tube made of paper was effective to reduce blast-vibration, while blast efficiency was decreased a little in the bottom of a blasthole. Wide Space blasting method has an advantage to control the fragmentation and to increase blast efficiency over conventional blasting methods. In this study new blasting method combining NDC blasting method and Wide Space blasting method was applied to the field, it was confirmed to reduce blast-vibration and increase blast efficiency. It is expected to make useful blasting method to cover the public complaints and to shorten construction time by accumulating blasting data using new method with various conditions.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.111-116
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• 1998

To construct transformed Bm5 cells, Autographa californica nuclear polyhedrosis virus (AcNPV)IE1 gene, an immediate early viral gene was firstly used in this study. AcNPV IE1 gene, which shares on 95.3% uncleotide sequence homology with Bombyx mori nuclear polyhedrosis virus (BmNPV) IE1 gene, was isolated and cloned into pBluescript. Neomycin gene from pKO-neo was inserted under the control of the IE1 promoter to yield pAcIE1-neo. The plasmid pAcIE1-neo was transfected into Bm5 or Sf9 cells, and neomycin-resistant cells were selected in TC100 medium containing 10% fetal bovine serum (FBS) and 1 mg/$m\ell$ G418 for two weeks. Individual clones were picked and each was amplified for further characterization. The genomic DNA from neomycin-resistnt cells was isolated and characterized by PCR using AcNPV IE1 gene-specific primers and by Southern blot analysis using neomycin gene probe. We concluded that AcNPV IE1 gene was functional in B. moridrived Bm5 cells as well as Spodaptera frugiperda-derived Sf9 cells to produce stably-transformed insect cells.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.387-394
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• 1994

To make the genomic DNA probe of Theileria sergenti, the merozoites were purified from bovine erythrocytes. The infected erythrocytes were lysed by Aeromonas hydrophila(Ah-1) hemolysin, and the parasites were isolated by ultracentrifugation on a Percoll discontinuous density gradient. For construction of a T sergenti genomic DNA library, T sergenti DNA was digested with Pstl and the fragments were ligated into the PstI site of pUC19 before transformation of Escherichia coli JM83. Out of thousands of transformants obtained by transformation of E coli JM83 with the genomic library, three plasmids were chosen. The sizes of the inserted DNAs were 2.9kb(2.4kb and 0.5kb) in pKTS1, 4.3kb in pKTS2 and 1.5kb in pKTS3, respectively. The DNA fragments used as probe KTS1(2.4kb), KTS2(4.3kb) and KTS3(1.5kb) were labeled digoxigenin-11-dUTP for the Southern hybridization. In Southern hybridization, all of the probes(KTS1, KTS2 and KTS3) reacted specifically to T sergenti DNA, but not to bovine leucocyte DNA. In order to find out the sensitivities of the digoxigenin-11-dUTP-labeled KTS1 and KTS3 as the probes, purified merozoite DNA and bovine DNA (control) were checked by dot blot hybridization with the probes. Both of the probes, KTS1 and KTS3, detected as minimum amount of 975pg of the T sergenti DNA, but not bovine DNA even to 500ng.

• Journal of Korean Society on Water Environment
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• v.33 no.1
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• pp.51-62
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• 2017

The purpose of this study is to evaluate on the applicability of Load Duration Curve (LDC) method using Maintenance of Variance Extension types 2 method and sampling data for efficient total maximum daily loads at the Nakbon-A unit watershed in Korea. The LDC method allows for characterizing water quality data such as BOD, TOC, T-N and T-P in this study at different flow regimes(or quarters). BOD usually exceeded the standard value (exceedance probability 50%) at low flow zone. On the other hand, TOC, T-N, T-P usually exceeded the standard value at dry and low flow zone. Seasonally all water quality variables usually exceeded the standard value at Q1(Jan-Mar) and Q2(Apr-Jun) zones. Improvement of effluent control from wastewater treatment plants are effective to improve BOD and T-P.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1483-1490
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• 2011

Electro-hydrostatic actuators(EHAs), which are usually composed of a direct motor-driven hydraulic pump and a cylinder, have been widely adopted as aircraft actuation systems because of their benefits in terms of improved efficiency, weight savings and the fact that they use a standalone power source. Since the recent trend in construction vehicles has been focus on energy savings in their hydraulic systems, EHAs are expected to be potential substitutes for conventional power transmission, since they are capable of energy recovery as well as highly efficient pump control. In this paper, the start and stop characteristics of EHAs were investigated through cracking pressure analysis of the pilot-operated check valve(PCV), which enables the cylinder to standstill against an external load with no holding effort from the hydraulic pump. A mathematical model that includes the load dynamics and the EHA's internal hydraulic circuit was derived for simulation with the MATLAB Simulink package. This model verified the PCV's opening and closing sequence, which in turn affects the EHA's start and stop characteristics.

• Journal of Korea Water Resources Association
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• v.37 no.3
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• pp.207-217
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• 2004

Our government is interested in the rehabilitation for the old sewer rather than the construction of a new sewer system. However, the research work on the sewer rehabilitation is not sufficient as much as the interest on the rehabilitation is increased. There are some research works for the determination of rehabilitation time by the genetic algorithm in Korea and foreign countries. However, the previous studies have considered the simple elements for the determination of the rehabilitation time and so the complex decision-making according to the degree of sewer superannuation has not been performed. Therefore, in this study, we estimate the capacity and Ⅰ/Ⅰ of sewer and determine the priority of the optimal rehabilitation for each outfall within the draining system. Also we develop the optimal rehabilitation decision making system for the cost estimation of optimal rehabilitation using the genetic algorithm.