• 제목/요약/키워드: Volume split

검색결과 113건 처리시간 0.024초

유한요소해석을 위한 하이브리드용접 입열모델 선정에 관한 기초적 연구 (Fundamental Study on The Heat Input Model of Hybrid Welding for The Finite Element Analysis)

  • 방한서;김영표
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2003년도 추계학술발표대회 개요집
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    • pp.36-38
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    • 2003
  • In order to understand the basic knowledge on the model of heat source in hybrid welding, authors have conducted finite element analysis to calculate heat distribution using three heat source models of non-split type and split type(Volume, Volume-Volume, Volume-Surface). From the research result, we can confirm that Volume-Volume heat source of split type is suitable for the analysis of heat distribution.

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동력 분배형 유성기어열의 구조 특성 분석 (Analysis of Structural Characteristics of Power-Split Type Planetary Gear Train)

  • 이기훈;이근호;배인호;이정상;정태형
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.311-314
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    • 2008
  • The volume and size of the wind turbine gearbox has been increased with increasing transmitted power. The optimal sizing of gearbox is important due to limited space on the nacelle. The power-split type planetary gear train has been regarded as a better solution than conventional type from the point of view of the volume and weight. The purpose of this paper is to optimize the volume and weight of the gearbox by the analysis of structural characteristics and evaluation of strength of the power-split type planetary gear train.

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쇄골 상부 림프절을 포함하는 왼쪽 유방암의 VMAT 치료계획시 X-Jaw split을 이용한 선량비교에 관한 연구 (Study on dose comparison using X-Jaw split in VMAT treatment planning for left breast cancer including supraclavicular lymph nodes.)

  • 김학준;이양훈;민제순
    • 대한방사선치료학회지
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    • 제33권
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    • pp.137-144
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    • 2021
  • 목 적 : VMAT을 이용한 쇄골 상부 림프절을 포함하는 왼쪽 유방암 치료 시 X-Jaw를 나눈 치료계획과 기존 Full field VMAT 치료계획과의 선량분포를 비교 분석하여 X-Jaw split VMAT의 유용성을 평가하였다. 대상 및 방법 : 쇄골 상부 림프절을 포함하는 왼쪽 유방암 환자 10명을 대상으로 Vacuum cushion을 이용하여 CT simulation 하고 2 Arc Full field VMAT과 4 Arc X-Jaw split VMAT을 각각 치료계획 하였다. 각 치료계획은 처방 선량(Prescription dose)이 치료계획표적용적(Planning Target Volume, PTV)의 95% 이상 포함이 되고 주변 정상장기(Organ at risk, OAR)에 최소한으로 조사되도록 설계하였다. 이후 선량체적용적(Dose volume histogram, DVH)을 통해 PTV과 OAR의 대한 선량분석을 하였다. 결 과 : 10명의 환자의 Full field VMAT치료계획과 X-Jaw split VMAT치료계획의 데이터를 평균값으로 나타내어 비교하였다. 처방선량지수(conformity index, CI) 1.05±0.04, 1.04±0.03, 선량균질지수(homogeneity index, HI) 1.07±0.008, 1.07±0.009 로 두 치료계획 간 차이는 크지 않았다. OAR의 경우 왼쪽 폐의 V5 56.1±6.50%, 50.4±6.30%, V20 20.0±4.15%, 13.52±3.61% 로 Full field VMAT대비 X-Jaw split VMAT에서 V5이 10.0% V20은 32.6% 감소하였다. 심장의 V30은 3.68±1.85%, 2.23±1.52%, 평균 선량은 8.93±1.65 Gy, 7.67±1.52 Gy로 X-Jaw split VMAT에서 V30은 39.3%, 선량은 14.1% 감소하였다. 정상조직인 왼쪽 폐와 심장은 통계적 유의 수치인 p-value 0.05미만으로 나타났다. 결 론 : PTV의 체적이 크고 X Jaw의 길이가 15 cm 이상이 되는 쇄골 상부 림프절을 포함하는 왼쪽 유방암치료의 경우 X-Jaw split VMAT 치료계획은 기존의 치료계획과 동등한 HI와 CI로 유사한 PTV coverage를 유지 하면서 개선된 선량분포를 나타내 OAR인 폐와 심장 등의 방사선량을 줄일 수 있어 부작용을 줄이는데 효과적이라고 생각된다.

Split tube 길이변화에 따른 스터링 극저온 냉동기의 특성에 관한 연구 (Study of Stirling Cryocooler Performance with different length of split tube)

  • 홍용주;박성제;고득용;김효봉;오군섭;김종학
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2001년도 학술대회 논문집
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    • pp.37-40
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    • 2001
  • A free piston and free displacer (FPFD) Stirling cryocooler for cooling infrared and cryo-sensor is currently under development at Korea Institute of Machinery & Materials. In this study, performance tests of stirling cryocooler with different length of split tube were performed to get characteristics of cryocooler. The Experimental results show the Stirling cryocooler with small volume of split tube has higher cooling power and faster response time.

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EFFECTS OF SPLIT INJECTION AND OXYGEN-ENRICHED AIR ON SOOT EMISSIONS IN A DIESEL ENGINE

  • Nguyen, Khai;Sung, Nak-Won;Lee, Sang-Su
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2965-2970
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    • 2008
  • Effects of split injection and oxygen-enriched air on soot emissions in a DI diesel engine were studied by the KIVA-3V code. When split injection is applied, the second injection of fuel into a cylinder results in two separate stoichiometric zones which increases soot oxidation. As a result, soot emissions are decreased with split injection. When oxygen-enriched air is applied together with split injection, higher concentration of oxygen helps secondary combustion which results in a higher temperature in the cylinder. The increased temperature promotes growth reaction of acetylene with soot but doesn't improve the acetylene formation during the second injection of fuel. As more acetylene is consumed in the growth reaction of acetylene, the net acetylene mass in the cylinder is decreased, which leads to a decrease of soot formation. With an increase of soot oxidation caused by split injection, the soot emissions are decreased significantly. However, to avoid excessive NOx emissions with increased oxygen concentration, the level of oxygen concentration should be lower than 22% in volume.

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Automatic Left Ventricle Segmentation using Split Energy Function including Orientation Term from CTA

  • Kang, Ho Chul
    • International journal of advanced smart convergence
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    • 제7권2호
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    • pp.1-6
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    • 2018
  • In this paper, we propose an automatic left ventricle segmentation method in computed tomography angiography (CTA) using separating energy function. First, we smooth the images by applying anisotropic diffusion filter to remove noise. Secondly, the volume of interest (VOI) is detected by using k-means clustering. Thirdly, we divide the left and right heart with split energy function. Finally, we extract only left ventricle from left and right heart with optimizing cost function including orientation term.

이동 객체 궤적의 최소경계사각형 영역을 효율적으로 분할하는 알고리즘에 관한 연구 (A Study on Efficient Split Algorithm for Minimum Bounding Box of Moving Object Trajectoty)

  • 박주현;조우현
    • 한국정보통신학회논문지
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    • 제17권1호
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    • pp.110-116
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    • 2013
  • 최근, 무선 네트워크의 발달로 인해 이동 객체에 대한 위치 정보를 수집하여 실생활에 활용하는 다양한 위치 기반 서비스의 증가하고 있다. 그에 따라서, 이동 객체의 연속적인 위치를 효율적으로 검색하는 새로운 색인 구조가 필요하게 되었다. 본 논문에서는 이동 객체의 좌표 사이의 거리가 긴 경우 탐색 공간을 줄이기 위해 효율적으로 분할하는 방법을 제안한다. 궤적의 적절한 분할 위치를 찾아서 평균적인 질의의 크기를 고려하여 형성되는 확장된 최소 경계 사각형(EMBR)의 영역을 이용한다. 추정 분할 방법은 최소경계 사각형을 최소화하게끔 고안되었고 이를 실험하였다. 실험 결과 제안하는 추정 분할 방법이 기존의 방법에 비해서 EMBR의 면적을 더 효율적으로 줄여줌을 알 수 있었다.

리눅스 클러스터 화일 시스템 SANiqueTM의 오류 회복 기법 (Failure Recovery in the Linux Cluster File System SANiqueTM)

  • 이규웅
    • 정보처리학회논문지A
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    • 제8A권4호
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    • pp.359-366
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    • 2001
  • This paper overviews the design of SANique$^{TM}$ -a shred file system for Linux cluster based on SAN environment. SANique$^{TM}$ has the capability of transferring user data from network-attached SAN disks to client applcations directly without the control of centralized file server system. The paper also presents the characteristics of each SANique$^{TM}$ subsystem: CFM(Cluster File Manager), CVM(Cluster Volume Manager), CLM(Cluster Lock Manager), CBM(Cluster Buffer Manager) and CRM(Cluster Recovery Manager). Under the SANique$^{TM}$ design layout, then, the syndrome of '||'&'||'quot;split-brain'||'&'||'quot; in shared file system environments is described and defined. The work first generalizes and illustrates possible situations in each of which a shared file system environment may split into two or more pieces of separate brain. Finally, the work describes the SANique$^{TM}$ approach to the given "split-brain"problem using SAN disk named "split-brain" and develops the overall recovery procedure of shared file systems.

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가스터빈 결합, 분리실린더, 등적.등압.등온 혼합사이클 엔진성능의 변수 분석 (A Parametric Analysis of Performance of Gas Turbine Combined, Split Cylinder, Constant Volume, Pressure, Temperature, Mixed Cycle Engine)

  • 김동호;배종욱
    • Journal of Advanced Marine Engineering and Technology
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    • 제28권7호
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    • pp.1082-1091
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    • 2004
  • Analyzed Parametrically was an internal combustion engine combined with gas turbine the cycle of which is splitted into compression side cylinder and expansion side one, and heat adding of which is during constant volume pressure, temperature process. The advantages of each measures were analyzed by means of thermal cycle diagram. The thermal efficiency of partial load cutting off firstly isothermal heat adding and secondly isobaric heat adding also was analyzed The authors suggested some potentials about the performance as for thermal efficiency, mean effective pressure and reducing emissions and noise supposed were the operating parameter of the engine set to some values and were some problems solved.

현장측정을 통한 기존 분기기용 목침목과 개량 분기기 부절침목의 동적거동 비교평가 (Dynamic Behavior Evaluation for Split PC sleeper using the Field Test)

  • 엄주환;이창훈;엄기영
    • 한국철도학회논문집
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    • 제9권6호
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    • pp.746-752
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    • 2006
  • The major objective of this study is to investigate the dynamic behavior evaluation of split PC sleepers for railway turnout by the field test. In railway engineering, a turnout is necessary to allow a vehicle to move from one track to another. So, turnout is required very complex railway technologies such as lolling stock, track. In reference to conventional line speed-up and improvement railway, accurate assembly of turnout affects travel ins qualify of turnout area and running safety. Because of heavy weight and a large volume of the long sleeper used to turnout and car limit, transport and the prerequisite for trouble-free transport of the factory pre-assembled major turnout components is achieved through division of long sleepers. The one of the advantages for using a split sleeper is to reduce the dynamic vibration according to the information of developed nations. Therefore, we investigate the characteristic of dynamic behaviors of split sleepers which are adopted for the first time to improve performance of turnout From the field test results of the split sleeper, it is evaluated that the modification of weight, material and stiffness compared with wood sleeper is very effective for the ballast safety. However, the decrease in vibration of split sleeper was not found out.