• Title/Summary/Keyword: Core Center

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Effect of Nitrogen Volume in Ar-N2 Shielding Gas on Microstructure and Hardness of GTA Welded Pure Ti (순 Ti GTA 용접부의 미세조직과 경도에 미치는 Ar-N2 보호가스 중 질소량의 영향)

  • An, Hyun-Jun;Jeon, Ae-Jeong;Hong, Jae-Keun;Jeong, Bo-Young;Lee, Jong-Sub;Kang, Chung-Yun
    • Journal of Welding and Joining
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    • v.30 no.2
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    • pp.70-75
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    • 2012
  • In this study, effect of nitrogen volume in the shielding gas of Ar-$N_2$ mixing gas on the bead shape, hardness and microstructure of GTA welds of 3mm thick Commercial Pure Ti was investigated. As the nitrogen volume increased, the welding current for full penetration was reduced and hardness in the fusion zone significantly increased compared with that of the base metal, but there is no difference in the hardness of HAZ. Microstructure in the fusion zone with pure Ar gas changed from equiaxed alpha of the base metal to serrated alpha. On the other hand, microstructure using Ar-$N_2$ mixing gas changed to acicular alpha. With the increasing of nitrogen content, the amount of acicular alpha increased and the size of that was fine.

Gene Expression Profiling in Rice Infected with Rice Blast Fungus using SAGE

  • Kim, Sang-Gon;Kim, Sun-Tae;Kim, Sung-Kun;Kang, Kyu-Young
    • The Plant Pathology Journal
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    • v.24 no.4
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    • pp.384-391
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    • 2008
  • Rice blast disease, caused by the pathogenic fungus Magnaporthe grisea, is a serious issue in rice (Oryza sativa L.) growing regions of the world. Transcript profiling in rice inoculated with the fungus has been investigated using the transcriptomics technology, serial analysis of gene expression (SAGE). Short sequence tags containing sufficient information which are ten base-pairs representing the unique transcripts were identified by SAGE technology. We identified a total of 910 tag sequences via the GenBank database, and the resulting genes were shown to be up-regulated in all functional categories under the fungal biotic stress. Compared to the compatible interaction, the stress and defense genes in the incompatible interaction appear to be more up-regulated. Particularly, thaumatin-like gene (TLP) was investigated in determining the gene and protein expression level utilizing Northern and Western blotting analyses, resulting in an increase in both the gene and the protein expression level which arose earlier in the incompatible interaction than in the compatible interaction.

Machinability Evaluation of Hybrid Ti2 Ceramic Composites with Conductivity in Micro Electrical Discharge Drilling Operation (전도성을 가지는 하이브리드 Ti2AlN 세라믹 복합체의 마이크로 방전드릴링에서 가공성 평가)

  • Heo, Jae-Young;Jeong, Young-Keun;Kang, Myung-Chang;Busnaina, Ahmed
    • Journal of Powder Materials
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    • v.20 no.4
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    • pp.285-290
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    • 2013
  • $Ti_2AlN$ composites are a laminated compounds that posses unique combination of typical ceramic properties and typical metallic(Ti alloy) properties. In this paper, the powder synthesis, SPS sintering, composite characteristics and machinability evaluation were systematically conducted. The random orientation characteristics and good crystallization of the $Ti_2AlN$ phase are observed. The electrical and thermal conductivity of $Ti_2AlN$ is higher than that of Ti6242 alloy. A machining test was carried out to compare the effect of material properties on micro electrical discharge drilling for $Ti_2AlN$ composite and Ti6242 alloy. Also, mixture table as a kind of tables of orthogonal arrays was used to know how parameter is main effective at experimental design. Consequently, hybrid $Ti_2AlN$ ceramic composites showed good machining time and electrode wear shape under micro ED-drilling process. This conclusion proves the feasibility in the industrial applications.

Effects of Welding Conditions and Material Arrangement on Tensile Properties of Friction Stir Lap Welded of Dissimilar Al Alloy, A5J32/A5052 (A5J32/A5052 이종 알루미늄 합금 겹치기 마찰교반접합부의 인장성질에 미치는 재료배열 및 접합조건의 영향)

  • Yoon, Tae-Jin;Kang, Myung-Chang;Kang, Chung-Yun
    • Journal of Powder Materials
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    • v.20 no.4
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    • pp.302-307
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    • 2013
  • A5J32-T4 and A5052-H32 dissimilar aluminum alloy plates with thickness of 1.6 and 1.5 mm were welded by friction stir lap welding (FSLW). The FSLW were studied using different probe length tool and various welding conditions which is rotation speed of 1000, 1500 rpm and welding speed of 100 to 600 mm/min and material arrangement, respectively. The effects of plunge depth of tool and welding conditions on tensile properties and weld nugget formation. The results showed that three type nugget shapes such as hooking, void, sound have been observed with revolutionary pitch. This plunge depth and material arrangement were found to effect on the void and hooking formation, which in turn significantly influenced the mechanical properties. The maximum joint efficiency of the FSLWed plates was about 90% compared to base metal, A5052-H32 when the A5052-H32 was positioned upper plate and plunge depth was positioned at near interface between upper and lower plates.

The Perceived Importance and Performance Frequency of Nursing Interventions in the Oncology Units in a Tertiary Hospital (종양내과병동에서의 간호중재 중요도 및 수행 빈도에 관한 연구 - 일 종합요양 전문기관을 중심으로 -)

  • Kwon, In Gak;Cho, Myung Sook;Shin, Hee Yeon
    • Korean Journal of Adult Nursing
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    • v.19 no.2
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    • pp.260-273
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    • 2007
  • Purpose: This study was performed to understand the perceived importance and performance frequencies of nursing interventions and identify the core and major interventions in oncology units. Methods: Questionnaires using 151 nursing interventions were given to 45 nurses. The performance frequency was measured through the database of the nursing process recording system for 1 year. Results: The perceived importance of the nursing interventions averaged out to be 3.5 among 4 and on average 36.5 times of nursing interventions were performed on each patient. Fifteen core nursing interventions including 'pain management' were identified and they made up 82.7% of the entire performance frequency rate. And 26 interventions including 'drug administration: Amphotericin-B' were identified as major nursing interventions and occupied 10.6% of the entire performance frequency rate. Conclusion: Since the core and the major nursing interventions were identified and these occupied 93.3% of the all nursing interventions, these results can be utilized as baseline data for establishing the guidelines and standards of nursing interventions and providing systematic education for oncology nurses in Korea.

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A Study on the Fork Exhibition Hall as Eco-museum Core Center in Chungbuk Area (지역의 정보발신지로서 충북지역 향토민속자료전시관에 대한 연구)

  • Bang, Han-Young;Choi, Hyo-Seung
    • Journal of the Korean Institute of Rural Architecture
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    • v.5 no.2
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    • pp.20-32
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    • 2003
  • In this study, I grasped the actual conditions of folk exhibition hall in Chungbuk area. From this data I researched basically as the fundamental role of regional museum, eco-museum core center facilities, the connection with islanded and various inheritances, and central facilities whole area to the museum. And I could get following conclusion. First, on the studied result of folk exhibition hall in chungbuk area, it is not enough the activity of unearthing, collection, study etc. that is basic activity of the museum because the museum just permanently displayed historical contents of the area and simple life folk data. Second, add to existent museum concept and have to widen viewpoint to the museum which whole area is no roof, and utilize folk exhibition hall as the central facilities. Specially, there are a lot of difficulties to communicate information to visitors because of the absence of cultural heritance exponent. So a plan that local resident participate actively in museum activity may have to be considered. Third, the concept of inheritance limited in historical culture of area has to be widening by nature and industry etc. And we should keep up study that is the linked plan to scattered conservation remains, inheritance and tourist place in area.

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Brake Performance Analysis of Sliding Mode Controller by Comparing with a Commercial Anti-lock Brake System (상용 ABS와 성능비교를 통한 슬라이딩 모드 제어기의 제동성능 분석)

  • Yun, Duk-Sun;Baek, Seung-Hwan;Kim, Heung-Sup;Song, Jung-Hoon;Boo, Kwang-Suck
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.2
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    • pp.14-23
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    • 2010
  • This paper analyzes braking performance of ABS with Sliding Mode Controller, which is designed in this research and compared with that of a commercial ABS-ECU only. HILS system for this paper has an existing hydraulic brake line with an ECU of commercial passenger vehicle and it is designed to be cooperated with Sliding Mode Controller and hydraulic line. This paper shows the simulation results to meet the target slip ratio on the various road conditions and displays the performance with Sliding Mode Controller has an improvement than a commercial ABS.

The Effect of Welding Condition on Tensile Properties of Friction Stir Welds of KS5J32 Al Alloy (KS5J32 Al합금 마찰교반접합부의 인장성질에 미치는 접합조건의 영향)

  • Yoon, Tae-Jin;Kim, Sang-Ju;Kim, Nam-Kyu;Song, Sang-Woo;Kang, Chung-Yun
    • Journal of Welding and Joining
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    • v.29 no.5
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    • pp.82-89
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    • 2011
  • The effect of welding condition on tensile properties of KS5J32 Al Alloy was investigated under various welding conditions. The 1.6 mm thick KS5J32 alloy sheets were joined by friction stir welding (FSW) technique with butt joint. The tool rotation speeds were 1000, 1250 and 1500 rpm, and the welding speeds were varied within the range from 100 to 600 mm/min. Voids mainly occurred at the advancing side of the tool probe, when the tool rotation speed was low, due to insufficient materials flow. When the weld pitch exceeded 0.4 mm/rev, voids were observed under all welding conditions and the area of voids increased with increasing weld pitch. For void-free specimens, fracture always occurred at base materials. However voids affected the location of fractures, base metal or welded zone, when the voids existed within the welds.

Responses of Arabidopsis thaliana to Challenge by Pseudomonas syringae

  • Kim, Min Gab;Kim, Sun Young;Kim, Woe Yeon;Mackey, David;Lee, Sang Yeol
    • Molecules and Cells
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    • v.25 no.3
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    • pp.323-331
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    • 2008
  • Plants are continually exposed to a variety of potentially pathogenic microbes, and the interactions between plants and pathogenic invaders determine the outcome, disease or disease resistance. To defend themselves, plants have developed a sophisticated immune system. Unlike animals, however, they do not have specialized immune cells and, thus all plant cells appear to have the innate ability to recognize pathogens and turn on an appropriate defense response. Using genetic, genomic and biochemical methods, tremendous advances have been made in understanding how plants recognize pathogens and mount effective defenses. The primary immune response is induced by microbe-associated molecular patterns (MAMPs). MAMP receptors recognize the presence of probable pathogens and evoke defense. In the co-evolution of plant-microbe interactions, pathogens gained the ability to make and deliver effector proteins to suppress MAMP-induced defense responses. In response to effector proteins, plants acquired R-proteins to directly or indirectly monitor the presence of effector proteins and activate an effective defense response. In this review we will describe and discuss the plant immune responses induced by two types of elicitors, PAMPs and effector proteins.

Coating Property of Hybrid Structured Photo-Electrode to Increase Dye-Sensitized Solar Cells Efficiency (염료감응형 태양전지의 효율 향상을 위한 하이브리드 구조 광전극의 코팅특성)

  • Kim, Min-Hee;Lee, Hyung-Woo;Jeong, Young-Keun
    • Journal of Powder Materials
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    • v.17 no.6
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    • pp.449-455
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    • 2010
  • The hybrid structured photo-electrode for dye-sensitized solar cells was fabricated based on the composites of $TiO_2$ nanoparticles and nanowires. Three samples with different hybrid structures were prepared with 17 vol%, 43 vol%, and 100 vol% nanowires. The energy conversion efficiency was enhanced from 5.54% for pure nanoparticle cells to 6.01% for the hybrid structure with 17 vol% nanowires. For the hybrid structured layers with high nanowires concentration (43 vol% and 100 vol%), the efficiency decreased with the nanowire concentration, because of the decrease of specific surface area, and of thus decreased current density. The random orientations of $TiO_2$ nanowires can be preserved by the doctor blade process, resulted in the enhanced efficiency. The hybrid structured $TiO_2$ layer can possess the advantages of the high surface area of nanoparticles and the rapid electron transport rate and the light scattering effect of nanowires.