• 제목/요약/키워드: interrupted

검색결과 705건 처리시간 0.026초

복잡 심기형에서의 동맥 전환술에 대한 연구 (Arterial Switch Operation in Complex Congenital Heart Diseaes (Application, procedure analysis,risk assessment,and results))

  • 김용진
    • Journal of Chest Surgery
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    • 제28권3호
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    • pp.237-246
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    • 1995
  • Between March 1989 and December 1994, one-stage repair was performed for correction of the intracardiac malformations associated with aortic coarctation in 34 patients or interrupted aortic arch in 8 patients via median sternotomy. There were 26 male and 16 female patients, and their body weight ranged from 1.8 to 8 kg [mean weight, 4.0 1.4 kg . The age at the operation ranged from 7 days to 18 months [mean age, 3.1 $\pm$ 3.8 months . The repair of aortic coarctation or interrupted aortic arch was performed using extended end-to-end anastomosis in most of the patients [86%, 36/42 , and six patients underwent ductal tissue excision and patch aortoplasty. Intracardiac defects were corrected concomitantly through the right atrium unless the anatomy dictated otherwise. Obstructive outlet septum was resected whenever necessary. There were seven early deaths [16.8 % , and three late deaths with a mean follow-up period of 25 months [range from 1 to 65 months . Three patients were reoperated upon residual subaortic stenosis, stenosis at the RPA origin, and subacute bacterial endocarditis respectively. None showed any significant residual or anastomotic stenosis postoperatively. One stage repair of the aortic coarctation and interrupted aortic arch associated with intracardiac defect leaves no native coarctation shelf tissue or residual hypoplasia in the repaired segment, has low incidence of recurrent or residual stenosis, minimizes reoperation and incisions, and manages arch hypoplasia easily. We concluded that surgical results of one-stage repair for the intracardiac malformation associated with aortic coarctation or interrupted aortic arch are reasonable.

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테이프가 있는 거친 사각채널에서 가열벽면의 수가 열전달에 미치는 효과 (Effects of Number of Heating Walls on Heat Transfer in the Rough Square Channel with Twisted Tape)

  • 안수환;김명호;배성택;강호근
    • 동력기계공학회지
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    • 제10권3호
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    • pp.17-22
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    • 2006
  • Surface modifications like rib-roughening and displaced insert devices like the twisted tape are commonly used in applications such as compact heat exchangers and cooling systems. In this paper, regionally averaged heat transfer distributions in square channels with twisted tape inserts and with twisted tape inserts plus interrupted ribs are respectively investigated. The square ribs are arranged to follow the trace of the twisted tape and along the flow direction defined as axial interrupted ribs. Each wall of the square channel is composed of isolated aluminum sections. Regionally averaged Nusselt number and channel averaged Nusselt number in turbulent air flows are presented for Reynold numbers from 8,900 to 29,000. We have obtained the following conclusions from the experimental study: 1) The local Nusselt number in the two-sided heated case is higher than that in the four-sided heated condition. 2) In the 4 heating wall channel with twisted tape inserts, Nusselt number based on bottom wall temperature is enhanced by 1.2 - 1.6 times if adding the axial interrupted ribs on the bottom wall only. 3) The twisted tape with interrupted ribs under the two-sided heating condition produces the highest heat transfer coefficient.

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기계구조용 탄소강(SM45C)의 단속절삭 시 절삭력예측을 위한 회귀방정식 도출 (Regression Equation Deduction for Cutting Force Prediction during Interrupted Cutting of Carbon Steel for Machine Structure (SM45C))

  • 배명일;이이선
    • 한국기계가공학회지
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    • 제15권4호
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    • pp.40-45
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    • 2016
  • Interrupted cutting has different cutting characteristics compared with continuous cutting. In interrupted cutting, the workpiece has a groove that regularly impacts the cutting tool and workpiece. Therefore, tool damage occurs rapidly, and this increases the cutting force and surface roughness. In this study, we performed interrupted cutting of carbon steel for machine structure (SM45C) using a coated carbide tool (TT7100). To predict the cutting force, we analyzed the experimental results with a regression analysis. The results were as follows: We confirmed that the factors affecting the principal force and radial force were cutting speed, depth of cut, and feed rate. From the multi-regression analysis, we deduced regression equations, and their coefficients of determination were 89.6, 89.27, and 28.27 for the principal, radial, and feed forces, respectively. This means that the regression equations were significant for the principal and radial forces but not for the feed force.

대동맥궁 단절을 동반한 Taussig-Bing 기형에서 새로운 일차적 완전 교정술 - 1례 보고 - (A New Method of One Stage Correction of Taussig-Bing Anomaly with Interrupted Aortic Arch -1 case report-)

  • 정종필;서동만
    • Journal of Chest Surgery
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    • 제30권1호
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    • pp.83-87
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    • 1997
  • Tausslg-Bing 기형은 드물게 대동맥궁 중단과 병발되며, 이 경우 양대혈관의 크기 가 현저히 달라 대동맥 전환술을 시행함에 어려움이 있다. 생후 20일 된 환아가 상기 진단으로 내원하여, 다장기부전에 대한 3주간의 집중관리 후 수술을 받았다. 수술은 심실중격 결손의 복원, 대동맥 전환술 및 광범위한 대동맥궁형성술로 이루어졌으며, 대혈관들의 크기 차이는 상행 및 하행 대동맥의 절편을 이용하여 원위신대동맥(distal neoaorta)를 형성하므로써 극복하였다. 환아는 큰 문제 없이 회복하였으며, 수술후 시행한 심도자상의 결과도 양호한 상태로 16개월간 추적 관찰중이다.

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고경도 금형강 단속 밀링절삭에 대한 CBN 공구의 가공 성능 (Machinability of CBN Tools in Interrupted Milling Process of Die & Mold Steels with High Hardness)

  • 송준희;문상돈
    • 대한금속재료학회지
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    • 제48권7호
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    • pp.651-659
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    • 2010
  • When high-speed interrupted cutting is carried out for die and mold steels with high hardness, CBN tools manifested a significantly longer wear life than carbide, ceramic, or cermet tools in an experiment of face milling characteristics. In addition, it was also found that they secured a stable surface roughness within a range of 1.6 S~6.3 S, an acceptable range for precision machining for polished machining parts. And it makes them acceptable in the precision machining field, except in industries where very high machining accuracy is required. In the high hardness interrupted cutting, it was advantageous to perform a negaland treatment and a honning treatment on the tools' cutting edge to extend tool life and surface roughness. Also, severe crater development was found on the sloped face in CBN tools following high-speed machining. This caused the cutting edge to be weakened and damaged, and ultimately resulted in a shorter tool life. Finally, as a result of EDX mapping inspection, Cr component was detected evenly on the entire crater wear area, which can be included only in STD 11.

The Effects of Social Support Perceived by Career-interrupted Women On Career Preparation Behavior: Focus on Mediating Effects of Career Decision Self-efficacy

  • Lee, Sook-Ja
    • 한국컴퓨터정보학회논문지
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    • 제24권12호
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    • pp.109-117
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    • 2019
  • 본 연구는 경력단절여성들의 인식을 바탕으로 진로에 영향을 미칠 수 있는 사회적 지지와 진로결정자기효능감이 진로준비행동에 미치는 영향과 진로결정자기효능감의 매개효과를 분석하였다. 여성취업지원기관에서 직업훈련에 참여하고 있거나 구직등록을 한 경력단절여성 227명을 대상으로 자기보고식 설문조사법을 이용하였다. 연구결과는 다음과 같다. 첫째, 경력단절여성들이 인식한 사회적 지지는 진로결정자기효능감과 진로준비행동에 유의미한 상관관계로 나타났다. 둘째, 사회적 지지의 하위요인 중 정서적 지지가 진로준비행동에 유의미한 영향을 미쳤다. 셋째, 진로결정자기효능감의 하위요인 중 목표설정과 직업정보는 진로준비행동에 유의미한 영향을 미쳤다. 넷째, 사회적 지지와 진로준비행동의 관계에서 진로결정자기효능감의 부분매개효과가 확인되었다. 본 연구결과는 경력단절여성들을 대상으로 진로지도 시 기술적인 측면보다 심리적 측면을 더 중요하게 다루어야 함을 시사해 준다.

DEVELOPMENT OF MATDYMO(MULTI-AGENT FOR TRAFFIC SIMULATION WITH VEHICLE DYNAMICS MODEL) II: DEVELOPMENT OF VEHICLE AND DRIVER AGENT

  • Cho, K.Y.;Kwon, S.J.;Suh, M.W.
    • International Journal of Automotive Technology
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    • 제7권2호
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    • pp.145-154
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    • 2006
  • In the companion paper, the composition and structure of the MATDYMO (Multi-Agent for Traffic Simulation with Vehicle Dynamic Model) were proposed. MATDYMO consists of the road management system, the vehicle motion control system, the driver management system, and the integration control system. Among these systems, the road management system and the integration control system were discussed In the companion paper. In this paper, the vehicle motion control system and the driver management system are discussed. The driver management system constructs the driver agent capable of having different driving styles ranging from slow and careful driving to fast and aggressive driving through the yielding index and passing index. According to these indices, the agents pass or yield their lane for other vehicles; the driver management system constructs the vehicle agents capable of representing the physical vehicle itself. A vehicle agent shows its behavior according to its dynamic characteristics. The vehicle agent contains the nonlinear subcomponents of engine, torque converter, automatic transmission, and wheels. The simulation is conducted for an interrupted flow model and its results are verified by comparison with the results from a commercial software, TRANSYT-7F. The interrupted flow model simulation is implemented for three cases. The first case analyzes the agents' behaviors in the interrupted flow model and it confirms that the agent's behavior could characterize the diversity of human behavior and vehicle well through every rule and communication frameworks. The second case analyzes the traffic signals changed at different intervals and as the acceleration rate changed. The third case analyzes the effects of the traffic signals and traffic volume. The results of these analyses showed that the change of the traffic state was closely related with the vehicle acceleration rate, traffic volume, and the traffic signal interval between intersections. These simulations confirmed that MATDYMO can represent the real traffic condition of the interrupted flow model. At the current stage of development, MATDYMO shows great promise and has significant implications on future traffic state forecasting research.

복잡 대동맥 교약증 또는 대동맥 차단증의 일차적 완전교정술에 대한 연구 (One-stage total Correction for Complex Aortic Coarctation and Interrupted Aortic Arch)

  • 김용진;전태국;노준량
    • Journal of Chest Surgery
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    • 제28권7호
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    • pp.658-665
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    • 1995
  • Between March 1989 and December 1994, one-stage repair was performed for correction of the intracardiac malformations associated with aortic coarctation in 34 patients or interrupted aortic arch in 8 patients via median sternotomy. There were 26 male and 16 female patients, and their body weight ranged from 1.8 to 8kg[mean weight, 4.0$\pm$l.4kg . The age at the operation ranged from 7 days to 18 months [mean age, 3.1$\pm$3.8 months . The repair of aortic coarctation or interrupted aortic arch was performed using extended end-to-end anastomosis in most of the patients[86%, 36/42 , and six patients underwent ductal tissue excision and patch aortoplasty. Intracardiac defects were corrected concomitantly through the right atrium unless the anatomy dictated otherwise. Obstructive outlet septurn was resected whenever necessary. There were seven early deaths[16.8% , and three late deaths with a mean follow-up period of 25 months [range from 1 to 65 months . Three patients were reoperated upon residual subaortic stenosis,stenosis at the RPA origin, and subacute bacterial endocarditis respectively. None showed any significant residual or anastomotic stenosis postoperatively. One stage repair of the aortic coarctation and interrupted aortic arch associated with intracardiac defect leaves no native coarctation shelf tissue or residual hypoplasia in the repaired segment, has low incidence of recurrent or residual stenosis, minimizes reoperation and incisions, and manages arch hypoplasia easily.We conclude that surgical results of one-stage repair for the intracardiac malformation associated with aortic coarctation or interrupted aortic arch are resonable.

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CA 모델을 활용한 단속류에서의 차량주행 특성 (Vehicle Running Characteristics for Interrupted Traffic Flow by Using Cellular Automata)

  • 정광수;도명식;이종달;이용두
    • 한국ITS학회 논문지
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    • 제11권6호
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    • pp.31-39
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    • 2012
  • 본 연구에서는 기존 기종점 트립 기반 교통시뮬레이션이 가지는 한계를 극복하고 대규모 지역이나 도시를 대상으로 개별 통행주체의 활동기반(activity-based) 모형의 적용가능성을 검증하기 위한 기초 연구로 단속류 가로구간을 대상으로 차량추종모형의 근간이 되는 가 감속 및 차로변경 등의 제어변수를 우리 실정에 맞게 보정(calibration)하는 방안을 제시하였다. 특히, 기존 한 cell의 크기인 7.5m보다는 1.0m가 단속류의 교통특성을 보다 잘 구현함을 확인하였으며 각 차량들에 ID를 부여하여 차량의 거동 특성을 추적하는 기법을 제시하였다. 나아가 차종을 세분화하고 대상구간의 차종비율을 적용시켜 실제 단속류에서의 차량의 주행특성을 분석하였다. 제안한 모델의 검증을 위해 대구시 수성구의 달구벌대로 일부 가로구간을 대상으로 시뮬레이션 한 결과 실제 단속류의 교통특성 구현이 가능함을 확인하였다.

Relationship between Speech Perception in Noise and Phonemic Restoration of Speech in Noise in Individuals with Normal Hearing

  • Vijayasarathy, Srikar;Barman, Animesh
    • Journal of Audiology & Otology
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    • 제24권4호
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    • pp.167-173
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    • 2020
  • Background and Objectives: Top-down restoration of distorted speech, tapped as phonemic restoration of speech in noise, maybe a useful tool to understand robustness of perception in adverse listening situations. However, the relationship between phonemic restoration and speech perception in noise is not empirically clear. Subjects and Methods: 20 adults (40-55 years) with normal audiometric findings were part of the study. Sentence perception in noise performance was studied with various signal-to-noise ratios (SNRs) to estimate the SNR with 50% score. Performance was also measured for sentences interrupted with silence and for those interrupted by speech noise at -10, -5, 0, and 5 dB SNRs. The performance score in the noise interruption condition was subtracted by quiet interruption condition to determine the phonemic restoration magnitude. Results: Fairly robust improvements in speech intelligibility was found when the sentences were interrupted with speech noise instead of silence. Improvement with increasing noise levels was non-monotonic and reached a maximum at -10 dB SNR. Significant correlation between speech perception in noise performance and phonemic restoration of sentences interrupted with -10 dB SNR speech noise was found. Conclusions: It is possible that perception of speech in noise is associated with top-down processing of speech, tapped as phonemic restoration of interrupted speech. More research with a larger sample size is indicated since the restoration is affected by the type of speech material and noise used, age, working memory, and linguistic proficiency, and has a large individual variability.