• 한국생산제조학회지
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• 제7권6호
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• pp.80-89
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• 1998

Back rake angle of tool is one of the fundamental effects to the cutting ability. In this paper, for several back rake angle of lathe tool (-5$^{\circ}$ , 0$^{\circ}$ , 5$^{\circ}$ , 10$^{\circ}$ , 15$^{\circ}$ ), we experimentally examine cutting forces via orthogonal cutting. Using measured cutting forces, a formula for specific cutting resistance is derived according to the variation of tool angle. Also, the measured cutting forces are analyzed in both time and frequency domain. Cutting parameters are obtained by measuring the thickness of chip, and the effect of the back rake angle of tool is manifested. This study maintains the predicted cutting model with improved accuracy.

• The Plant Pathology Journal
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• 제20권1호
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• pp.22-29
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• 2004

Many important horticultural and field crops are susceptible to virus infections or may possess a degree of resistance to some viruses, but become infected by others. Plant viruses enter cells through the presence of wounds, and replicate intracellularly small genomes that encode genes required for replication, cell-to-cell movement and encapsidation. There are numerous evidences from specific virus-host interactions to require the involvement of host factors and steps during viral replication cycle. However, viruses should deal with host defense responses either by general or specific mechanisms, targeting viral components or genome itself. On the other hand, the host plants have also adapted to defend themselves against viral attack by operating different lines of resistance responses. The defense-related interactions provide new insights into the complex molecular strategies for hosts for defense and counter-defense employed by viruses.

• 펄프종이기술
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• 제32권4호
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• pp.10-17
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• 2000

The change of fiber length, freeness, initial forming drainage velocity, specific filtration resistance, final drainage time and wet web dryness were measured to investigate the effect of the refining load on the drainage characteristics of pulp. The arithmetic average fiber length after refining with higher refining load was shorter than that obtained with lower refining load. Higher refining load decreased initial forming drainage velocity, final drainage time and wet web dryness. The refining load also affected the relationship between freeness and specific filtration resistance, initial forming drainage velocity, final drainage time. It was found that the specific filtration resistance is better than freeness to predict the drainage characteristics of pulp and the wet dryness.

• 대한화학회지
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• 제7권2호
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• pp.182-185
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• 1963

In the previous paper of the series of researches on the graphitic properties of anthracites, authors have already reported the results on the electrical specific resistance measurements for Korean anthracites in order to develope a simple methods which differentiate graphite from anthracite. In this paper, the X-ray diffraction method and oxidation have been applied and compared with the results which were obtained by the specific resistance measurements in the previous paper. It has been confirmed that there is a parallel relation between the value of specific resistance measurement and height of hexagonal peak by X-ray diffraction, but the color reaction due to graphitic acid by oxidation does not show any definite critical points between graphite and anthracite.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.206-207
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• 2006

This paper describes the dielectric analysis of several insulators for home appliances. The dielectric characteristics of ABS(acrylonitrile butadiene styrene) were tested in relative permittivity, dielectric loss($tan{\delta}$) and specific resistance and compared with those of the other 4 insulators of PE(polyethylene) series. As a result, the relative permittivity of only the ABS slightly decreased with temperature. In the case of the tan6, the ABS showed higher dielectric loss than the other insulators but more excellent thermal performance. In addition, its changing pattern in specific resistance was very similar to that in $tan{\delta}$.

• 한국육종학회지
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• 제40권3호
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• pp.215-222
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• 2008

Fifty-two Korean japonica rice cultivars were analyzed for leaf blast resistance and genotyped with 4 STS and 26 SSR markers flanking the specific chromosome sites linked with blast resistance genes. In our analysis of resistance genes in 52 japonica cultivars using STS markers tightly linked to Pib, Pita, Pi5(t) and Pi9(t), the blast nursery reaction of the cultivars possessing the each four major genes were not identical to that of the differential lines. Eight of the 26 SSR markers were associated with resistant phenotypes against the isolates of blast nursery as well as the specific Korean blast isolates, 90-008 (KI-1113), 03-177 (KJ-105). These markers were linked to Pit, Pish, Pib, Pi5(t), Piz, Pia, Pik, Pi18, Pita and Pi25(t) resistance gene loci. Three of the eight SSR markers, MRG5836, RM224 and RM7102 only showed significantly associated with the phenotypes of blast nursery test for two consecutive years. These three SSR markers also could distinguish between resistant and susceptible japonica cultivars. These results demonstrate the usefulness of marker-assisted selection and genotypic monitoring for blast resistance of rice in blast breeding programs.

• The Plant Pathology Journal
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• 제38권6호
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• pp.616-628
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• 2022

Resistance to pyraclostrobin due to a single nucleotide polymorphism at 143rd amino acid position on the cytochrome b gene has been a major source of concern in red pepper field infected by anthracnose in Korea. Therefore, this study investigated the response of 24 isolates of C. acutatum and C. gloeosporioides isolated from anthracnose infected red pepper fruits using agar dilution method and other molecular techniques such as cytochrome b gene sequencing, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and allele-specific polymerase chain reaction (PCR). The result showed that four isolates were resistant to pyraclostrobin on agar dilution method and possessed GCT (alanine) codon at 143rd amino acid position, whereas the sensitive isolates possessed GGT (glycine). Furthermore, this study illustrated the difference in the cytochrome b gene structure of C. acutatum and C. gloeosporioides. The use of cDNA in this study suggested that the primer Cacytb-P2 can amplify the cytochrome b gene of both C. acutatum and C. gloeosporioides despite the presence of various introns in the cytochrome b gene structure of C. gloeosporioides. The use of allele-specific PCR and PCR-RFLP provided clear difference between the resistant and sensitive isolates. The application of molecular technique in the evaluation of the resistance status of anthracnose pathogen in red pepper provided rapid, reliable, and accurate results that can be helpful in the early adoption of fungicide-resistant management strategies for the strobilurins in the field.

• 한국생산제조학회지
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• 제19권1호
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• pp.128-133
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• 2010

The Titanium has many superior characteristics which are specific strength, heat resistance, corrosion resistance, organism compatibility, non-magnetic and etc. and their quantity are abundant. this study performed turning operation of Ti-6Al-4V alloy using the TiAlN Coated Tool which treated Physical Vapor Deposition. Experimental works are also executed to measure cutting force, tool wear, chip figuration and surface roughness for different cutting conditions. As a result of study. Cutting depth influences on the cutting force much more than the feed rate and the value of the cutting force is the most stable at the depth of 1.0mm. And tool wear was serious at over 100m/min of cutting speed and cutting condition was excellent at 1.0mm of cutting depth.

• ETRI Journal
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• 제34권1호
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• pp.134-137
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• 2012

Power metal-oxide semiconductor field-effect transistor (MOSFET) devices are widely used in power electronics applications, such as brushless direct current motors and power modules. For a conventional power MOSFET device such as trench double-diffused MOSFET (TDMOS), there is a tradeoff relationship between specific on-state resistance and breakdown voltage. To overcome the tradeoff relationship, a super-junction (SJ) trench MOSFET (TMOSFET) structure is studied and designed in this letter. The processing conditions are proposed, and studies on the unit cell are performed for optimal design. The structure modeling and the characteristic analyses for doping density, potential distribution, electric field, width, and depth of trench in an SJ TMOSFET are performed and simulated by using of the SILVACO TCAD 2D device simulator, Atlas. As a result, the specific on-state resistance of 1.2 $m{\Omega}-cm^2$ at the class of 100 V and 100 A is successfully optimized in the SJ TMOSFET, which has the better performance than TDMOS in design parameters.

• 한국기계가공학회지
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• 제3권4호
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• pp.81-87
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• 2004

The titanium has many superior characteristics such as specific strength, heat resistance, corrosion resistance, organism compatibility, non-magnetic and etc. and their quantity are abundant. This study performed turning operation of Ti-6Al-4V alloy using the TiAlN coated tool which was treated with PVD. Experimental works were also executed to measure cutting force, chip figuration and surface roughness for different cutting conditions. As a result of study, tool wear was serious at the condition over 100m/min of cutting speed. The excellent cutting condition of cutting depth was at 1.0mm.