• Title/Summary/Keyword: Fusion line

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A Study on the Impact Toughness and Microstructure change for Low carbon TMCP Structural Steel Alloy with Welding Heat Impact (용접 입열량에 따른 저탄소형 TMCP 구조용 강재의 용접부 충격인성 및 미세조직 변화에 관한 연구)

  • Gwon Sun Du;Lee Gwang Hak;Park Dong Hwan
    • Proceedings of the KWS Conference
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    • v.43
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    • pp.101-102
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    • 2004
  • This study was investigated on the impact toughness and microstructure of welded metal and heat affected zone for B grade steel. With welding procedures, welding heat inputs applied were 30, 79 and 264 kJ/cm, Prior austenite grain size in coarse zone has increased with increasing welding heat input for B grade steel. The toughness of fusion line zone of Bgrade steel has decreased with increasing welding heat input while the toughness fusion line +3 and +5 mm zone increased contrarily.

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Evaluation of Microstructural and Mechanical Properties of SA508 cl.3 Heat Affected Zone Produced by RPV Cladding

  • Lee, J.S.;Kim, I.S.;Kwon, S.C.
    • Proceedings of the Korean Nuclear Society Conference
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    • 2004.10a
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    • pp.867-868
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    • 2004
  • The maximum width of HAZ of SA508치.3 steel produced by overlay RPV cladding was approximately 10 mm and it was composed of variety of microstructures with various grain size and precipitates. In addition, along the weld fusion line there formed a heavy carbide precipitation zone in the width of $20{\sim}30\;{\mu}m$. 2. As the specimen sampling position approached to the weld fusion line, the increase in yield and tensile strength was approximately 90 and 40 MPa, respectively. Meanwhile, the plastic fracture strain reduced from 14 to 8 percent. 3. The lowest SP energy and the highest ductile to brittle transition temperature in the HAZ were observed at the coarse- and fine-grained HAZ.

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A Study on Creep Crack Growth Behavior of Weld Interface Crack (용접 계면균열의 크리프 균열성장 거동에 관한 연구)

  • 윤기봉;김광웅;정용근
    • Journal of Welding and Joining
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    • v.16 no.4
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    • pp.83-91
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    • 1998
  • Cracking problems which high temperature plant components suffer during long-term service, occur very often at welded locations. The crack occurs due to accumulated creep damage near fusion line or at heat affected zone (HAZ). However, most of the studies on creep crack growth behavior have been performed with matrix metal not wit welded metal due to the difficulty of interpreting the test results. In this study, creep crack growth rates were measured with C(T) specimens whose cracks were formed along the fusion line or HAZ. The measured crack growth rates were characterized by {TEX}$C_{t}${/TEX}-parameter derived for elastic-primary-secondary creeping material. Since contribution of primary creep was significant for the tested 1Cr-0.5Mo steel, its effect was carefully studied. Effects of crack tip plasticity and material aging were also discussed.

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The Effect of Weld Metal Copper Content on HAZ Cracking in Austenitic Stainless Steel welded with Al-brass

  • Lee, H.W.;Lee, J.S.;Choe, W.H.
    • Proceedings of the KWS Conference
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    • 2005.06a
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    • pp.152-154
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    • 2005
  • Austenitic stainless steel has good weldability but is sensitive to hot cracking such as solidification crack and liquation crack. In this study, the specimens of dissimilar metals made between austenitic stainless steel and Al-brass were welded by GTAW process using four different filler metals. Cracks were detected in the heat-affected zone of the stainless steel when welded with CuAl, CuSn and NiCu filler metals, but no cracks were detected a Ni filler metal was used. The cracks propagated along the grain boundary in the heat affected zone near the fusion line to base metal of 316L stainless steel. The cracks were located inside the weld bead with very fine hairline crack. All cracks initiated at the fusion line and moved forward in the base metal. From energy dispersion spectroscopy (EDS), Cu peak was detected only in the crack-opening area.

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TREATMENT OF FUSED PERMANENT MANDIBULAR LATERAL AND CENTRAL INCISORS: REPORTS OF CASES (유합된 하악 영구 중절치와 측절치의 치료에 관한 증례보고)

  • Han, Jeong-Jae;Kim, Dae-Eop;Lee, Kwang-Hee
    • Journal of the korean academy of Pediatric Dentistry
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    • v.24 no.4
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    • pp.795-804
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    • 1997
  • Developmental dental morphological anomalies are fusion, gemination, twinning, concrescence and etc. They may cause many problems in conservative, periodontal and esthetic aspects. Fusion is a condition where two separate tooth buds unite at some stage in their development to form a bifid crown. If tooth contact occurs early, at least before the start of calcification, the two teeth may be completely unites to form a single large tooth. If tooth contact occurs after the time when a portion of the tooth crown has completed its formation, there may be union of the roots only. In fusion the dentin is always confluent. Fusion teeth is more common in the deciduous than in the permanent dentition. Fused teeth are relatively rare, and are mostly mandibular anterior teeth. Fusion of normal and supernumerary teeth or between normal teeth may occurs. The exact etiology factor of fusion is unknown, but genetic and environmental factors seems to be related. A variety of complications and subsequent treatments have been suggested on this teeth. Periodontal conditions may arise due to a groove formed at the line of fusion of the two teeth. Crowding or Protrusion with potential for malocclusion or delayed eruption of adjacent teeth. Fusion teeth appear in the anterior region, they usually cause esthetic problems. Treatments vary depending on the problem, the location, and the extent of fusion. Treatment of fused teeth has been reported from endodontic, orthodontic, periodontic, surgical and multidisciplinary. This report presents the esthetic improvements by separation of two clinical crowns. Bone reduction or endodontic treatments are not required.

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Immunotherapeutic Effects of CTLA4Ig Fusion Protein on Murine EAE and GVHD (마우스 EAE, GVHD 질환에서 CTLA4Ig 융합단백의 면역치료 효과)

  • Jang, Seong-Ok;Hong, Soo-Jong;Cho, Hoon-Sik;Chung, Yong-Hoon
    • IMMUNE NETWORK
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    • v.3 no.4
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    • pp.302-309
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    • 2003
  • Background: CTLA4 (CD152), which is expressed on the surface of T cells following activation, has a much higher affinity for B7 molecules comparing to CD28, and is a negative regulator of T cell activation. In contrast to stimulating and agonistic capabilities of monoclonal antibodies specific to CTLA-4, CTLA4Ig fusion protein appears to act as CD28 antagonist and inhibits in vitro and in vivo T cell priming in variety of immunological conditions. We've set out to confirm whether inhibition of the CD28-B7 costimulatory response using a soluble form of human CTLA4Ig fusion protein would lead to persistent inhibition of alloreactive T cell activation. Methods: We have used CHO-$dhfr^-$ cell-line to produce CTLA4Ig fusion protein. After serum free culture of transfected cell line we purified this recombinant molecule by using protein A column. To confirm characterization of fusion protein, we carried out a series of Western blot, SDS-PAGE and silver staining analyses. We have also investigated the efficacy of CTLA4Ig in vitro such as mixed lymphocyte reaction (MLR) & cytotoxic T lymphocyte (CTL) response and in vivo such as experimental autoimmune encephalomyelitis (EAE), graft versus host disease (GVHD) and skin-graft whether this fusion protein could inhibit alloreactive T cell activation and lead to immunosuppression of activated T cell. Results: In vitro assay, CTLA4Ig fusion protein inhibited immune response in T cell-specific manner: 1) Human CTLA4Ig inhibited allogeneic stimulation in murine MLR; 2) CTLA4Ig prevented the specific killing activity of CTL. In vivo assay, human CTLA4Ig revealed the capacities to induce alloantigen-specific hyporesponsiveness in mouse model: 1) GVHD was efficiently blocked by dose-dependent manner; 2) Clinical score of EAE was significantly decreased compared to nomal control; 3) The time of skin-graft rejection was not different between CTLA4Ig treated and control group. Conclusion: Human CTLA4Ig suppress the T cell-mediated immune response and efficiently inhibit the EAE, GVHD in mouse model. The mechanism of T cell suppression by human CTLA4Ig fusion protein may be originated from the suppression of activity of cytotoxic T cell. Human CTLA4Ig could not suppress the rejection in mouse skin-graft, this finding suggests that other mechanism except the suppression of cytotoxic T cell may exist on the suppression of graft rejection.

Design of Fusion Multilabeling System Controlled by Wi-Fi Signals (Wi-Fi신호로 제어되는 융합형 다중라벨기 설계)

  • Lim, Joong-Soo
    • Journal of the Korea Convergence Society
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    • v.6 no.1
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    • pp.1-5
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    • 2015
  • In this paper, we describe the design of a fusion labeling system which is controlled by the Wi-Fi signals. The Current labeling system which is used in the industry is designed to work independently on the production line not connected with internet network services. For such reasons, it is very inconvenient for the labeling system to transfer such labeling data of the production line to the server computer. We propose a labeling system connected to the Wi-Fi service being able to send real-time transmission of labeling data. This system can supply the labeling data of production line to the server computer in realtime and improve the production quality than the existing system.

Broad Band Stop Filter Using Frequency Selective Surface Embeded in Microwave Transmission Line (마이크로파 전송선로에 삽입된 주파수 선택 표면을 이용한 광대역 대역저지필터)

  • Kim, Jinyoung;Jung, Changwon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.12
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    • pp.6022-6026
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    • 2012
  • This article presents a band-stop filter (BSF) by using a periodic structure property of frequency selective surfaces (FSSs) embedded in a microstrip transmission line. The proposed BSF is designed with FSS unit cells modifying the cross-loop slots. The BSF is interpreted with an equivalent circuit model and a dispersion diagram. The center frequency (fo) of the BSF is 6.6GHz. Proposed filter increases the number of unit cell. As a result, 3dB bandwidth is wider and insertion loss is reduced. Also, Facbricated BSF exhibits uniplanar geometry, simple fabrication.

On-Line Travel Time Estimation Methods using Hybrid Neuro Fuzzy System for Arterial Road (검지자료합성을 통한 도시간선도로 실시간 통행시간 추정모형)

  • 김영찬;김태용
    • Journal of Korean Society of Transportation
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    • v.19 no.6
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    • pp.171-182
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    • 2001
  • Travel Time is an important characteristic of traffic conditions in a road network. Currently, there are so many road users to get a unsatisfactory traffic information that is provided by existing collection systems such as, Detector, Probe car, CCTV and Anecdotal Report. This paper presents the results achieved with Data Fusion Model, Hybrid Neuro Fuzzy System for on - line estimation of travel times using RTMS(Remote Traffic Microwave Sensor) and Probe Data in the signalized arterial road. Data Fusion is the most important process to compose the various of data which can present real value for traffic situation and is also the one of the major process part in the TIC(Traffic Information Center) for analyzing and processing data. On-line travel time estimation methods(FALEM) on the basis of detector data has been evaluated by real value under KangNam Test Area.

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