• 제목/요약/키워드: barrel

검색결과 541건 처리시간 0.021초

포배열카메라 영상을 활용한 함포 사격통제시스템의 동적배열오차 분석 및 보정방법 (Study on Analyzing and Correction of Dynamic Battery Alignment Error in Naval Gun Fire Control System by using Image of Boresight Telescope)

  • 김의진;서태일
    • 한국군사과학기술학회지
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    • 제16권6호
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    • pp.745-751
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    • 2013
  • In naval gun firing, firing accuracy comes from the combination of each component's accuracy in CFCS (Command and Fire Control System) like tracking sensors and gun. Generally, battery alignment is done to correct the error between gun and tracking sensor by using boresight telescope on harbor and sea. But normally, the battery alignment can compensate only the static alignment error and ignore dynamic alignment error which is caused by own ship movement. There was no research on this dynamic alignment error until now. We propose a new way to analyze dynamic arrangement error by using image of boresight telescope. In case of the dynamic alignment error was due to time delay of own ship attitude information, we propose the way to compensate it.

1970년대의 석유위기가 해운산업에 미친 영향 (The Impact of the Oil Crisis on the Shipping Industry)

  • 민성규
    • 한국항해학회지
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    • 제6권2호
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    • pp.65-75
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    • 1982
  • During the last decade the world had experienced oil crisis twice: the first one was the fourfold jump in oil prices in 1973 and 1974, the second one came in 1979 with 2.6 times price hike. The current crude oil prices stand around the level of $30 a barrel. The first reaction came quick, with reduced oil consumption and a general decline in economic activity. Furthermore, the second oil crisis has brought about tremendous and varied impacts upon the shipping industry, which is now undergoing an adaptation process to the changing environments. This article is divided into five chapters: chapter I is the introduction on the subject under examination; chapter II is devoted to the trends of the seaborne trade cargoes after the oil crisis; chapter III reveals the impact of the oil price hike on ships and their desion; chapter IV deals with the challenges shipping enterprises face in terms fo economic modus operandi and new international political environments; chapter V sets forth conclusion.

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다중날을 가진 스크류의 최적화 설계 (The optimum Design of the Multi-flight Screw using Finite Element Analysis)

  • 최동열;조승현;김청균
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2001년도 제33회 춘계학술대회 개최
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    • pp.248-256
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    • 2001
  • Capacities of screw are pumping, steady flow of polymer melts, volumetric efficiency, steady volumetric throughout etc. they are affected by geometry of screw, heat flux, pressure on inside barrel, rotating velocity, friction coefficient at screw surface etc. Also the temperature of polymer melts by heating pad and injection pressure play a very important role in the injection molding machine. by computation volumetric efficiency increases as rotating velocity increases, flight number increses, and decreases as friction coefficient increases. but volumetric throughout is different :s flight number increases with helix angle variability. so in this paper we analyze thermal distortion and stress of screw includes pressure and temperature distributions by finite element analysis to understand what design factors influence on thermo-mechanical characteristics of screw.

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사출기 스크류와 배럴의 접촉거동 특성에 대한 연구 (A Study on Contact Dynamic Characteristics of Screw and Barrels in Injection Molding Machine)

  • 최동열;고영배;조승현;김청균;주성규
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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    • pp.212-220
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    • 2000
  • Single flighted screw extrusion is the most cost effective method for the production of film, sheet, pipe and the fundamental step in other processes including blow molding and injection molding. The temperature of polymer melts and injection pressure play a very important role in the injection molding machine. Thermal distortion and displacement of screw by temperature difference and injection pressure difference cause adhesive wear by metal-to-metal contact. In this paper we analyze thermal distortion and stress of screw includes pressure and temperature distributions by finite element analysis to understand dynamic characteristics of screw.

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A Case with Spondyloepiphyseal Dysplasia Tarda with TRAPPC2 Mutation

  • Kim, Hyun-Jin;Lee, Beom-Hee;Kim, Yoo-Mi;Kim, Gu-Hwan;Kim, Ok-Hwa;Yoo, Han-Wook
    • Journal of Genetic Medicine
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    • 제9권1호
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    • pp.31-34
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    • 2012
  • Spondyloepiphyseal dysplasia tarda (SEDT) is an X-linked skeletal dysplasia. Patients show disproportionate short stature with short trunk and barrel-shaped chest, which usually become pronounced in late childhood. The radiologic findings are characterized by narrow intervertebral disc spaces and moderate epiphyseal dysplasia of long bones. Here we report a case of SEDT with a novel frameshift mutation in TRAPPC2, the disease-causing gene of SEDT. This is the first Korean report with SEDT confirmed by genetic testing.

발전소 복수기 볼세정계통에 의한 입형펌프 진동과 대책 (Vibration Phenomena between Condensate Vertical Pump and Condenser Debris system in Power Plant)

  • 김연환;구재량;배용채;이현;이영신
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
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    • pp.1020-1025
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    • 2001
  • Vertical canned pumps are usually applied in the power plant to transport fluids that the available suction pressure is low at the condensate system and the circulating-water system. The top of the motor driver is 5.5m above the base and the barrel and drop column extend even further below the ground. While this size and configuration may produce an efficient pumping system, it also introduces several dynamic problems which must be considered in order to obtain a reliable operation. The main problem is that the vibrational mode of the long flexible cantilever structure above the ground exist near the operational characteristics of the condensate debris system. This system's trouble has been showed at 2,086 hp condensate water loading pumps in a nuclear power plant.

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Performance of a RBSN under RCP Scenarios in Korea

  • 권유정;서용원
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2018년도 학술발표회
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    • pp.124-124
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    • 2018
  • 본 연구에서는 과거 강우자료 (1971-2000)와 대표농도경로 RCP 4.5와 8.5 (2071-2100)를 사용하여 RBSN(Rain Barrel sharing Network)의 효과를 비교 검토 하였다. IPCC 5차 평가 보고서에 의하면 앞으로의 기후변화에 있어 우리나라의 강수량은 온실가스 배출량을 저감에 관계없이 증가할 것으로 예상된다. 이것은 활용가능한 수자원이 늘어나지만, 장마와 집중호우로 인한 피해가 증가할 수도 있는 점을 나타낸다. 이와 같은 미래 기후 변화에 효과적으로 대응하기 위한 방법으로 RBSN을 적용하여 과거 강우자료와 온실가스 시나리오 하에서의 성능을 비교하였다. RBSN의 성능을 평가하는 기준으로 신뢰성, 복원탄력성, 취약성을 사용하였다. 분석 결과 RBSN 적용 시 네트워크의 증가에 따른 신뢰성과 취약성은 기후변화 시나리오 하에서 각각 3.44%, 49.18% 향상되었고, 복원 탄력성이 16.73% 감소하는 것으로 나타났다.

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Meconium Peritonitis: A Rare Treatable Cause of Non-Immune Hydrops

  • Rajendran, Usha Devi;Govindarajan, Jeyanthi;Balakrishnan, Umamaheswari;Chandrasekaran, Ashok;Amboiram, Prakash
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제22권6호
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    • pp.576-580
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    • 2019
  • Meconium peritonitis as a cause of non-immune hydrops in neonates is rarely reported. Here we report such a rare occurrence. In our case, a routine antenatal scan at 25 weeks revealed isolated ascites. By 31 weeks of gestation, all features of hydrops were observed in scans. However, antenatal workup for immune and non-immune hydrops was negative. Subsequently, a preterm hydropic female baby was delivered at 32 weeks. She required intubation and ventilator support. An X-ray revealed calcification in the abdomen suggestive of meconium peritonitis. Ultrasound showed gross ascites, a giant cyst compressing the inferior vena cava, and minimal bilateral pleural effusion. Emergency laparotomy revealed meconium pellets and perforation of the ileum. Double-barrel ileostomy was performed, and the edema resolved and activity improved. The baby was discharged after 3 weeks. Ileostomy closure was done at follow-up. The baby is growing well.

유가상승에 따른 철도 물류의 발전 방안에 대한 기초 연구 (Preliminary Study on Development Strategies of Railroad Logistics by Rising of Oil Price)

  • 박은수;전영준;구자경;이태식
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 추계학술대회 논문집
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    • pp.782-788
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    • 2008
  • Present Prices have reduced to $100 per barrel, but international oil prices caused big damage to local logistics industry due to rise in International oil prices and, in august 2008 oil prices reached up to 146 US. Depending on oil prices, the domestic logistic industry should develop a strategy by innovative management of purchase of supply for manufacturing industry and efficient supply and demand of resources which is believed to be more important. Accordingly, we want to analyze railroad logistics' present condition and effect on railroad industry that can expect affirmative development by oil-price rise and by developing strategies for efficient railroad logistics.

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KALIMER 원자로구조물의 면진성능 및 내진여유도 평가

  • 유봉;구경회;이재한
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 추계학술발표회논문집(2)
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    • pp.683-689
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    • 1996
  • 본 논문의 목적은 현재 국내에서 개념설계중인 KALIMER(Korea Advanced LIquid MEtal Reactor) 원자로구조물에 대한 면진성능과 내진여유도를 평가하여 이들 성능을 향상시킬 수 있는 주요 설계변경 부위를 검토하는 것이다. 이를 위하여 ANSYS 범용 유한요소해석코드를 이용하여 원자로구조물에 대한 3차원 유한요소해석모델을 작성하고 이로부터 집중질량 스프링으로 이루어진 지진해석모델을 개발하여 지진해석을 수행하였다. KALIMER 원자로 구조물에 대한 내진평가결과 내진능력(Seismic Capability)은 0.35g로 나타났으며 이는 Reactor Vessel Liner, Separation Plate그리고 Support Barrel의 연결부위의 수직 강성을 증가시키는 설계변경을 통하여 크게 향상될 수 있는 것으로 나타났다.

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