• 제목/요약/키워드: HCr

검색결과 47건 처리시간 0.019초

스테인리스 304 슬라브의 HCR 조건시 열적/기계적 거동 (Thermo-Mechanical Behavior of Type 304 Stainless Slab in Hot Charge Rolling Condition)

  • C.G. Sun;S.M. Hwang
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2003년도 추계학술대회논문집
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    • pp.183-186
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    • 2003
  • A finite element-based, integrated process model is presented for a three dimensional, coupled analysis of the thermal and mechanical behavior of type 304 stainless slab during hot charge rolling (HCR) and cold charge rolling (CCR) processes. The validity of the proposed model is examined through comparison with measurements. The susceptibility on micro-crack initiation or propagation due to the thermal stress in these two different process conditions was examined. The model's capability of revealing the effect of diverse process parameters is demonstrated through a series of process simulation.

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Hybrid Coronary Revascularization Using Limited Incisional Full Sternotomy Coronary Artery Bypass Surgery in Multivessel Disease: Early Results

  • Kang, Joonkyu;Song, Hyun;Lee, Seok In;Moon, Mi Hyung;Kim, Hwan Wook;Jo, Gyun Hyun
    • Journal of Chest Surgery
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    • 제47권2호
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    • pp.106-110
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    • 2014
  • Background: There are several modalities of coronary artery revascularization for multivessel coronary artery disease. Hybrid coronary revascularization (HCR) with minimally invasive direct coronary artery bypass grafting was introduced for high-risk patients, and recently, many centers have been using it. Limited incisional full sternotomy coronary artery bypass (LIFCAB) involves left internal thoracic artery (LITA)-to-left anterior descending coronary artery (LAD) anastomosis through a sternotomy with a minimal skin incision; it could be considered another technique for minimally invasive LITA-to-LAD anastomosis. Our center has performed HCR using LIFCAB, and in this paper, we report our short-term results, obtained in the past 3 years. Methods: The medical records of 38 patients from May 2010 to June 2013 were analyzed retrospectively. The observation period after HCR was 1 to 37 months (average, $18.3{\pm}10.3$ months). The patency of revascularization was confirmed with postoperative coronary angio-computerized tomography or coronary angiography. Results: There were 3 superficial wound complications, but no mortalities. All the LITA-to-LAD anastomoses were patent in the immediate postoperative and follow-up studies, but stenosis was detected in 3 cases of percutaneous coronary intervention. Conclusion: HCR using LIFCAB is safe and yields satisfactory results from the viewpoint of revascularization for multivessel disease.

다수차고지와 예약시간 위반을 고려한 교통약자 차량 서비스에 대한 연구 (A Study for Solving Multi-Depot Dial-a-Ride Problem Considering Soft Time Window)

  • 김태형;박범진;강원의
    • 한국ITS학회 논문지
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    • 제11권5호
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    • pp.70-77
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    • 2012
  • 교통약자들을 위한 차량서비스는 dial-a-ride, demand responsive 또는 paratransit으로 불리며 미국과 유럽에서 널리 제공되고 있는 대중교통의 하나이다. 본 연구는 이러한 교통약자 차량서비스의 배차와 차량경로문제에 관한 것으로 다수차고지와 예약시간 위반을 고려한다. 본 연구에서는 기존의 연구에서 제안된 clustering first-routing second에 기초한 휴리스틱 알고리즘을 실제 큰 규모의 교통약자 차량서비스에 적용하였다. 사례연구로서 Maryland Transit Administration (MTA)의 교통약자 차량서비스를 소개하고 실제 MTA의 운영결과와 제안된 휴리스틱 알고리즘의 결과를 비교하였다. 제안된 모형의 목적함수는 서비스제공자의 비용과 고객들의 불편비용으로 이루어진 전체비용을 최소화하는 것이다. 실제 MTA의 운영자료에 차량대기시간, 서비스지연시간과 초과승차시간에 대한 정보가 없는 관계로 비교를 위해서 clustering first-routing second에 기초한 휴리스틱 알고리즘의 목적함수 값은 차량의 대기비용, 고객들의 서비스지연비용과 초과 승차시간 비용를 포함하지 않는다. MTA의 실제운영에 의한 목적함수 값보다 HCR의 목적함수 값이 보다 나은 것으로 나타났으며 이 결과는 본 연구에서 제안된 휴리스틱 방법이 실제운영을 보다 효율적으로 바꿀 수 있음을 보여준다.

수소크롬산 이온에 의한 옥살라토아쿠아몰리브덴(IV) 삼합체의 산화반응 (Kinetic Studies on the Oxidation of Oxalatoaquamolybdenum(IV) Trimer by Hydrogen Chromate Ion)

  • 김창수;권창룡
    • 대한화학회지
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    • 제30권1호
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    • pp.57-62
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    • 1986
  • HCr$O_4^-$에 의한 $[Mo_3O_4(C_2O_4)_3(H_2O)_3]^{2-}$의 산화는 몰리브덴(IV)화합물, $[Mo_2O_5(C_2O_4)_2(H_2O)_2]^{2-}$를 생성한다. HCr$O_4^-$$[Mo_3O_4(C_2O_4)_3(H_2O)_3]^{2-}$의 반응에 대한 화학양론은 $2Mo_3^{IV} + 4Cr^{VI} {\to} 3Mo_2^{VI} + 4Cr^{III}$와 같다. 관찰된 속도상수는 수소이온농도에 의존한다.$Cr^{VI}$$Cr^V$$Cr^{IV}$를 거쳐서 $Cr^{III}$로 일전자씩 연속적으로 변화한다. 상세한 메카니즘이 논의된다.

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Bullet Train of Giant Nonlinear Internal Waves from Luzon Strait

  • Liu, Cho-Teng;Hsu, Ming-Kuang;Chen, Hsien-Wen;Wang, Dee-Way;Chyou, Yuan-Jie;Lee, Chang-Wei
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.934-937
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    • 2006
  • In the northeastern South China Sea (SCS), fast westward moving (about 2.9 m/s) non-linear internal waves (NLIWs) are emanated nearly daily from the Luzon Strait. Their propagation speed is faster than NLIWs previously observed in the deep water of world oceans, their amplitude of 140 m or more is the largest free propagating NLIWs so far observed in the deep ocean. These NLIWs energized the top 1500 m of the water column, heaving it up and down in 20 min. Their associated energy density and energy flux are the largest observed to date. During 2005 and 2006 experiment, they were found west of the HengChun Ridge (HCR) that links Luzon and Taiwan Islands. This coincides with founding in satellite images, no NLIW front was found east of HCR. But, the turbulent environment east of HCR may prohibit surface signature of NLIWs that were emanated from sills between Batan Islands. The relative contribution of the two ridges on NLIW in Luzon Strait is still under study.

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땅콩 근류균(根瘤菌)(Bradyrhizobium sp. HCR-46) 접종이 Cowpea군(群) 두과작물(豆科作物)의 질소고정(窒素固定)에 미치는 영향(影響) (Effect of Inoculation of Peanut Bradyrhizobium sp. HCR-46 on the Nitrogen Fixation of Cowpea Group Legume)

  • 최윤희;이상복;정지호;소재돈
    • 한국토양비료학회지
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    • 제25권4호
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    • pp.378-386
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    • 1992
  • Cowpea군(群) 두과작물(豆科作物)에 대한 땅콩근류균(根瘤菌) HCR-46의 근류형성능(根瘤形成能) 및 질소고정능(窒素固定能)을 검토(檢討)하고자 동부, 녹두, 팥, 땅콩에 무접종(無接種)+N : 0kg/10a, 무접종(無接種)+N : 6kg/10a, 접종(接種)+N : 0kg/10a, 접종(接種)+N : 6kg/10a, 접종(接種)+N : 12kg/10a로 처리(處理)하여 시험(試驗)한 결과(結果) 초기근류형성시기(初期根瘤形成時期)는 팥이 가장 빠르고 동부, 녹두, 땅콩순(順)이었으며 질소(窒素)를 증시(增施)할 수록 지연(遲延)되는 경향(傾向)이었다. 근류수(根瘤數)와 근류중(根瘤重)은 생육(生育)이 진행(進行)될 수록 증가(增加)하였고, 질소(窒素)를 증시(增施)할 경우 땅콩을 제외한 동부, 녹두, 팥에서 감소(減少)하였다. 건물생산량(乾物生産量)과 질소흡수량(窒素吸收量)은 균접종구(菌接種區)가 무접종구(無接種區)에 비(比)해 높았고 균접종시(菌接種時)는 질소무시용구(窒素無施用區)에 비(比)해 질소(窒素) 6kg/10a 시용구(施用區)가 높았다. 접종균(接種菌)에 의해 고정(固定)된 질소량(窒素量)은 파종후(播種後) 60일(日) 질소무시용구(窒素無施用區)의 동부, 녹두, 팥, 땅콩이 각각(各各) 39.32, 42.39, 28.07, 78.56mg/주(株) 이었고 질소(窒素)6kg/10a 시용구(施用區)에서는 각각(各各) 25.46, 24.97, 16.80, 47.65mg/주(株)로서 질소무시용구(窒素無施用區)가 질소(窒素)6kg/10a시용구(施用區)에 비(比)해 많아 균접종효과는 질소시용구(窒素施用區)보다는 무시용구(無施用區)에서 뚜렷했다.

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Comparison of the Ligating Ability of Anonic Transition Metal Complex $(Mn(CO)_{5}{^-})$, Transition Metal Hydrides $(HCr(CO)_{5}{^-},\;HW(CO)_{5}{^-},\;cis-HW(CO)_{4}P(OMe)_{3}{^-},\;HFe(CO)_{4}{^-},\;trans-\;HFe(CO)_{3}P(OMe)_{3}{^-})$, and Traditional Ligands $(Br^-,\;P(C_{6}H_{5})_{3})\;to\;M(CO)_{5}{^0}$ (M = Cr, W)

  • Park, Yong K;Han, In S;Marcetta Y. Darensbourg
    • Bulletin of the Korean Chemical Society
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    • 제15권6호
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    • pp.436-442
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    • 1994
  • Heterobimetallic complexes have a donor-accepter metal-metal bond in which two electrons from the electron-rich metal moiety are donated to the other electron-deficient one. Based on the competition reactions, Cotton-Kraihanzel force constants, ν(CO)IR band resolution and the relative nucleophilicity comparison of the donor ligands, the following relative ligating ability of the donor ligands toward $M(CO)_5$ (M=Cr, W) is assessed: cis-HW$(CO)_4P(OMe)_3^-$, $HW(CO)_5^-$ > $HCr(CO)_5^-$-$Br^-$ > trans-HFe$(CO)_3P(OMe)_3^-$ > $Mn(CO)_5^-$ > $HFe(CO)_4^-$ > PP$h_3$

A New Dynamic HRA Method and Its Application

  • Jae, Moosung
    • International Journal of Reliability and Applications
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    • 제2권1호
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    • pp.37-48
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    • 2001
  • This paper presents a new dynamic human reliability analysis method and its application for quantifying the human error probabilities in implementing management action. For comparisons of current HRA methods with the new method, the characteristics of THERP, HCR, and SLIM-MAUD, which are most frequency used method in PSAs, are discussed. The action associated with implementation of the cavity flooding during a station blackout sequence is considered for its application. This method is based on the concepts of the quantified correlation between the performance requirement and performance achievement. The MAAP 3.0B code and Latin Hypercube sampling technique are used to determine the uncertainty of the performance achievement parameter. Meanwhile, the value of the performance requirement parameter is obtained from interviews. Based on these stochastic obtained, human error probabilities are calculated with respect to the various means and variances of the things. It is shown that this method is very flexible in that it can be applied to any kind of the operator actions, including the actions associated with the implementation of accident management strategies.

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Comparison of Coronary Artery Bypass Graft-First and Percutaneous Coronary Intervention-First Approaches for 2-Stage Hybrid Coronary Revascularization

  • Choi, Hang Jun;Kang, Joonkyu;Song, Hyun;Kim, Do Yeon;Choi, Kuk Bin
    • Journal of Chest Surgery
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    • 제50권4호
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    • pp.247-254
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    • 2017
  • Background: Hybrid coronary revascularization (HCR) was developed to combine the advantages of coronary artery bypass graft (CABG) with percutaneous coronary intervention (PCI). However, it is still controversial whether it is more optimal to perform CABG or PCI first. The purpose of this study was to compare the clinical outcomes of these 2 approaches. Methods: Eighty patients who underwent HCR from May 2010 to December 2015 were enrolled in this retrospective analysis. The CABG-first group comprised 12 patients and the PCI-first group comprised 68 patients. Outcomes of interest included in-hospital perioperative factors, major adverse cardiac and cerebrovascular events (MACCEs), and the incidence of repeated revascularization, especially for the target vessel lesion. Results: No significant difference was found in the amount of postoperative bleeding (p=0.239). The incidence of MACCEs was similar between the CABG-first and PCI-first groups (1 of 12 [8.3%] vs. 5 of 68 [7.4%], p>0.999). Repeated revascularization was performed on 3 patients (25%) in the CABG-first and 9 patients (13.2%) in the PCI-first group (p=0.376). Conclusion: There were no significant differences in postoperative and medium-term outcomes between the CABG-first and PCI-first groups. Based on these results, it can be inferred that it is safe to opt for either CABG or PCI as the primary procedure in 2-stage HCR.

Transgenic mouse embryo를 이용한 human HoxA 유전자의 조절부위 분석과 전후축 형태형성(anterior-posterior axial pattern formation)에 미치는 영향 (Analysis of human HoxA gene control region and its effects on anterior-posterior axial pattern formation using transgenic mouse embryo)

  • 장승익;민원기;박종훈;이철상;이경광;이영원;전무형;김명희
    • 대한수의학회지
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    • 제35권1호
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    • pp.95-105
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    • 1995
  • The human homolog of position specific element of mouse Hoxa-7 was studied using transgene. It contains a 1.1 kb human DNA (HCR)- a homolog to the intergenic region between Hoxa-7 and -9, which directs the position specific expression of Hoxa-7-, tk promoter, LacZ (${\beta}$-galactosidase) gene as a reporter, and polyadenylation signal of SV40 large T antigen. It was injected into the mice embryos, and the resulting transgenic embryos were analysed through PCR as well as genomic Southern blotting with placenta DNA. Out of 20 embryos analysed, two were transgenic. Among them, one transgenic embryo expressed transgene when stained with X-gal. The expression pattern was in analogy to that of the mouse Hoxa-7, showing spatially restricted expression pattern, Since the expression of ${\beta}$-galactosidase is regulated by the upstream human HCR sequence, it implies that the HCR is the plausible position specific regulatory element of human.

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