• 제목/요약/키워드: time-lapse

검색결과 472건 처리시간 0.024초

복합제 초 저상 굴절버스의 충돌 특성 해석 (Crashworthiness Characteristic Analysis of Composite Non-step Bus)

  • 김유석;최정훈;조진래;이상진
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.756-761
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    • 2007
  • This papered is concerned with the crashworthiness characteristics analysis of the non-step bus when it is crashed or roll-over analysis. Computer simulations is implemented using LS-Dyna explicit code which can effectively analysis dynamic response with the lapse of time. We construct a FEM model of the non-step bus under development according to the safety rules used in Europe for composite non-step buses. The crash energy and absorption rate are evaluated to understand crashworthiness characteristic of the composite non-step bus. Body deformation is also examined whether the survival space is secured for passengers.

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경년열화 최소화를 위한 심타 접지공법에 관한 연구 (A Study on a New Grounding Methods to Minimize Deterioration with the Lapse of Time)

  • 김근환;왕윤찬;박중신
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.539-541
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    • 2005
  • 본 연구의 목적은 배전선로에서 운용중인개폐기, 변압기, 피뢰기 등의 규정 접지저항을 확보코자 시행하는 접지공사에 필요한 접지봉을 땅속 깊이 시공할 수 있는 접지봉의 개발과 접지봉 시공용 기계식 타격장치를 개발 활용하는 효율적, 경제적인 접지공법을 연구함에 있다. 또한 접지봉의 경년열화특성을 최소화하고자 접지봉의 접속부 구조를 개선하여 경년열화 특성을 향상하는데 있다. 특히, 굴착이 곤란한 도심지에서 최소 면적만을 굴착하여 규정 접지저항을 확보하는 방법을 제시하고 접지의 설계 및 시공 둥 실무에 활용할 수 있도록 하였다.

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개에서 Tetrachlorethylene에 의해 유발된 간장 병변의 임상 및 초음파학적 연구 (Clinical and Ultrasonographic Studies for the Liver Lesion Induced by Tetrachlorethylene in Dogs)

  • 김영범;김명철
    • 한국임상수의학회지
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    • 제16권2호
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    • pp.321-327
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    • 1999
  • This study was performed to examine the clinical, serological, ultrasonographic and pathological findings in dogs with acute liver disease induced by tetrachlorethylene at 4 times of anthelminthic oral dose. The results obtained through this experiment could be summarized as follows: 1. The dogs administered with tetrachlorethylene, revealed decreased body weight, and showed lethargy and depression. 2. In serological findings, bilirubin values slightly increased, AST and ALT was decreased at 1∼3 days, and after that time increased according to the lapse of days, and revealed the highest at 5 days, and decreased to normal values at 6 days. 3. In ultrasonographic findings, branches of the portal vein were increased, the echodensity of the liver parenchyma was decreased at early stage, and increased at mid stage, and decreased at last stage. 4. In histopathological findings, necrosis of parenchymal cell, and perivascular hemorrhage were observed more severely at 6 days, as compared with 3 days. There results suggest that ultrasonographic examination is considered to be a more simple, rapid, non-invasive and useful diagnostic method for acute liver parenchymal lesion.

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식이성(食餌性) 인삼(人蔘)이 백서혈액(白鼠血液) ethanol의 청소율(淸掃率)에 관(關)한 효과(效果) (EFFECT OF DIETARY PANAX GINSENGS ON THE RATE OF THE BLOOD ETHANOL CLEARANCE)

  • 장이수
    • 대한한방내과학회지
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    • 제1권1호
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    • pp.92-97
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    • 1976
  • Upon feeding dried Ginseng to rats of either low-protein or high protein diet ethanol was administered intraperitoneally and disappearance rate blood alcohol was enzymatically measure. In terms of residual blood alcohol after a time lapse of 3.5 hours between intraperitonial administration and blood withdrawal neither ginseng nor ginseng plus 40% casein did improve the rate, of alcohol clearance but sexual difference was clearly demonstrated in favor of female rats. In the case of blood withdrawn only 2 hours after intraperitoneal injection of alcohol, the tendency of female superiority in alcohol clearance rate is demonstrated when a comparison is made among the groups fed with ginseng and this was particularly true is groups of rats fed with basal diet plus 1 percent ginseng residual blood ethanol being 15.4 mg/ml vs. 8.8 mg/ml. Liver homogenate alcohol dehydrogenase activity measured in terms of residual ethanol content after in vitro reaction on which a known amount of alcohol was added clearly demonstrated a male superiority in alcohol clearance.

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조기강도 콘크리트의 현장적용을 위한 고성능감수제의 종류에 따른 특성 연구 (Study on the Field Application According to the Early Strength of the Concrete Admixed with Polycarboxylate Superplasticizer)

  • 이진우;김경민;이영환;배연기;이재삼
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.671-674
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    • 2005
  • In this study, it is examined the properties of early strength of concrete mixed with polycarboxylate superplasticizer. For this experiment, it is analyzed that the slump and strength properties according to the mixture factors, compared with cements and superplasticizers of each company and curing temperature($15,\;20^{\circ}C$). (1) The slump loss of concrete used polycarboxylate superplasticizer(rapid strength type) showed $0.5\~1.5cm$, it is judged that slump loss according to the time lapse can be minimized. (2) The performance of polycarboxylate superplasticizer kept up consistency and accelerated strength development. it is possible to reveal 12MPa within $18\~20$hours at $20^{\circ}C$ curing, but impossible within 24hours at $15^{\circ}C$. (3) It is necessary to studies about rapid strength development in the low temperature.

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스월유동장의 화염전파에 미치는 난류특성의 영향에 관한 연구 (A study on the influence of turbulence characteristics on flame propagation in swirl flow field)

  • 이상준;이종태;이성열
    • 대한기계학회논문집B
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    • 제20권10호
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    • pp.3282-3292
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    • 1996
  • Flow velocity was measured using a hot wire anemometer. Turbulence intensity was in proportion to mean flow velocity regardless of swirl velocity. And integral length scale has proportional relation with swirl velocity regardless of measurement position. Flame speed calculated by radius of visualized flame was increased and then decreased according to lapse of time from spark. Maximum flame speed was increased according to increase of turbulence intensity. Burning speed and flame transport effect increased with increase of swirl velocity, but ratio of burning speed to flame speed decreased with increased of swirl velocity. Mass fraction burned versus volume fraction burned was increased in proportion to the increase of turbulence intensity, caused by increase of combustion promotion effect according to increase of turbulence intensity and scale.

전단유동에서 입자의 운동 (Migration of a heavy particle in uniform shear flow)

  • 조성기;이창훈
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1903-1908
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    • 2003
  • The motion of a small, heavy rigid particle in the shear flow on a stationary wall is investigated in the context of Stokes flow. The lift force proposed by Saffman(1965) and later modified by Mclaughlin(1991) and Mei(1992) is considered in the prediction of the particle motion far away from the wall. Later, the expression of the lift force is modified to take into account the effect of wall(Cherukat and Mclaughlin, 1994). In the analysis the gravity and buoyancy effect are also taken into account. An analytical and numerical results for the terminal velocities and trajectories of the particle after the enough lapse of time are presented.

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Numerical discrepancy between serial and MPI parallel computations

  • Lee, Sang Bong
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제8권5호
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    • pp.434-441
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    • 2016
  • Numerical simulations of 1D Burgers equation and 2D sloshing problem were carried out to study numerical discrepancy between serial and parallel computations. The numerical domain was decomposed into 2 and 4 subdomains for parallel computations with message passing interface. The numerical solution of Burgers equation disclosed that fully explicit boundary conditions used on subdomains of parallel computation was responsible for the numerical discrepancy of transient solution between serial and parallel computations. Two dimensional sloshing problems in a rectangular domain were solved using OpenFOAM. After a lapse of initial transient time sloshing patterns of water were significantly different in serial and parallel computations although the same numerical conditions were given. Based on the histograms of pressure measured at two points near the wall the statistical characteristics of numerical solution was not affected by the number of subdomains as much as the transient solution was dependent on the number of subdomains.

Monitoring of artificial infiltration using electrical resistivity method

  • Nakazato Hiroomi;Kuroda Seiichiro;Okuyama Takehiko;Takeuchi Mutsuo;Park Mikyung;Kim Hee Joon
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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    • pp.362-369
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    • 2003
  • A infiltration experiment of river water has been conducted to evaluate the applicability of electrical resistivity monitoring methods in an area containing gravelly deposits in Nagaoka, Japan. Apparent resistivity data, which are inverted to obtain the resistivity distribution, are measured with a newly developed system. This system can collect 490 data in an hour and be controlled with PC to store the data. Subsurface resistivity sections, which are obtained from two-dimensional nonlinear inversion of time-lapse apparent resistivity data, enable us to estimate the direction of the flow and the rate of infiltration. The infiltration rate is estimated to be $4.4{\times}10^4m/s$ in the early stage of the experiment when the infiltration process is dominant.

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반추동물에 있어서 침술의 진통 및 해열효과 (Analgesic and Antipyretic Effects of Acupucture in Ruminant)

  • 남치주;권오경;서강문
    • 한국임상수의학회지
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    • 제11권1호
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    • pp.393-399
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    • 1994
  • This study was carried out to investigate the analgesic and antipyretic effects of acupuncture in goat suffered from pain and fever induced experimentally : electroacupuncture and laser acupuncture for the relief of pain and traditional needing for the of fever. Pain was induced by intraperitoneal injection of 0.7% acetic acid solution and it's extent was estimated with the number of writhing syndrom as indicator of pain. When lipopolysaccharide was given into the vein in goat, fever with biphasic type was produced. In the goats with pain the superior analgesic effects of electroacupuncture to aminopyrine and sulpyrine were found, but the effects of laser acupuncture were not satisfactory. The high body temperature of goats was gradually decreased with the lapse of time following traditional needling(venesection by needle) and showed a tendency to return to normal body temperature. Serum GOT, GPT:, BUN, creatinine values and acetylcholinesterase activity following electroacupuncture were not altered. It is considered that electroacupuncture combined with medicament can sucure exellent analgesic and antipyretic effects in animal practice.

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