• Title/Summary/Keyword: transition region

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A Study on the Release Rate of Hazardous Materials from Liquid Pipeline (액체배관으로부터 위험물질 누출속도 산정에 관한 연구)

  • Tak Song-Su;Jo Young-Do
    • Journal of the Korean Institute of Gas
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    • v.6 no.1 s.17
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    • pp.81-85
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    • 2002
  • This paper presents the calculation methods of liquid release rate in the transition region when hazardous materials leak from the pipeline due to an unwanted accident. For the laminar and turbulent flow region, liquid release rate from a pipeline can be calculated by using a commercial software or by using calculator based on the models(equations) suggested by Crowl and Louvar et al. However, there has been no corresponding model for the transition flow region. In this paper. we showed that the turbulent model may be used as an equation generally used in the transition region for conservative hazard analysis if safety factor $30\%$ is added to the value calculated by the turbulent model. In this regard, we first calculated the release rate from liquid pipeline in the transition region by using experimental data on Fanning friction factor depending on Reynolds number which Lap-Mou Tam et al. had introduced, then compared it with that of the laminar and turbulent models in transition region.

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Chain Dimensions and Intrinsic Viscosities of Polypeptides in the Helix-Coil Transition Region

  • Jong-Ryul Kim;Tai-Kyue Ree
    • Bulletin of the Korean Chemical Society
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    • v.4 no.1
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    • pp.36-41
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    • 1983
  • An equation is derived which correlates the unperturbed dimensions $_0$ of polypeptides with the helical contents in the helix-coil transition region by using a simple model of a polypeptide chain. The model is a chain of connected balls which represent the repeating units, -CO-NH-CHR-, based on the fact that the repeating unit has a plane structure. The changing trend of the expansion factor ${\alpha}_{\eta}$ in the transition region is connected with the helical content $f_H$. The intrinsic viscosities [${\eta}$] of polypeptides are calculated from the unperturbed dimensions and the ${\alpha}_{\eta}$ factors. The above calculated results concerning $_0$ and [${\eta}$] are compared with other authors' theoretical and experimental results. From the comparison, we concluded that our theory explains better the chain dimensional behavior of polypeptides in the helix-coil transition region than others.

Vascular Transition and Hypocotyl Elongation in Soybean(Glycin max) Seedlings (대두(Glycine max) 유식물에서 하배축의 신장과 유관속전이)

  • 강경덕
    • Journal of Plant Biology
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    • v.34 no.4
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    • pp.274-281
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    • 1991
  • The relationship between elongation of hypocotyl and its vascular transition was studied with seedling of Glycine max. the hypocotyl elongation proceeded acropetally from the base of hypocotyl toward the cotyledonary node. The vascular transition did not occur in the basal region of the hypocotyl, which did not nearly elongate, with exarch radial vascular bundles. However, the vascular transition was almost completed at the middle part of the hypocoty, more or less elongated, with endarch collateral vascular bundles. Such bundles also appeared in the uppermost region of the hypocotyl, in which the elongation was the most striking. These results suggested that the vascular transition was related to the hypocotyl elongation and that the transition of primary vascular system in Glycine max seedling was established by rather rapid process. Our observations of the serial sections from root to hypocotyl revealed that the vascular system through the root-hypocotyl-cotyledon was a unit, to which one of the epicotyl that did not participate in transition was superimposed.

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Effect of Welding Condition on Microstructure of Transient Zone in Overlay Weld of 3Cr-1Mo Steel/STS-309L (3Cr-1Mo강/STS-309L 오버레이 용접부의 천이영역 조직에 미치는 용접조건의 영향)

  • 김동진;김병훈;지병하;김정태;김성곤;강정윤;박화순
    • Journal of Welding and Joining
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    • v.18 no.2
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    • pp.49-56
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    • 2000
  • Recently developed Austenite stainless steel, 309L was used to overlay on 3Cr-1Mo-V-Ti-B steels, using Electroslag welding process, which wide electrodes were adopted. Transition region in welding interlayer relating to disbonding crack was investigated. Also, the effect of welding condition on the width of transition region and coarsening grains of the austenite were studied. 1) With increasing welding speed the width of martensite at transient region was increased, but the amount of delta ferrite in weld metal was reduced, being fine grained. 2) The form of martensite at the transition region was occurred by reversible transformation during cooling since the interdiffusion of Cr and Ni from weld metal and Fe and C from base metals at the transition region, causes to lowering the concentration of Cr and Ni at the transition region, leading to increasing Ms point. 3) With increasing welding speed, the grain of austenite formed at the welding interface was finer. With increasing welding current under the same welding speed, the grain size of the austenite was finer. At high current, original grain size of the austenite is coarse, but the austenite has fine grains because the austenite was transformed to martensite during cooling. 4) In the case of high welding speed, the width of martensite at the welding interface was increased, but the grain size of austenite at the welding interface was finer. This indicates that the inhibition of disbonding crack may be achieved through dispersening fine carbides in the gain boundary.

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Detection of Conflict Transition Scene Using Character Regions (인물 면적을 이용한 갈등 전환 장면 검출)

  • Park, Seung-Bo;Lee, Chang-Hyun
    • Journal of Broadcast Engineering
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    • v.26 no.5
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    • pp.543-552
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    • 2021
  • The story is formed by the flow of the development and resolution of the conflict between the characters. Namely, the story consists of conflict setting, development, and resolution. Character region is an important expression technique to describe the emotions or states of characters and the relationship between characters and the environment. The purpose of this paper is to propose a method for detecting the transition of conflict from the graph of character region's change. To this end, we present a method of generating a change graph of a character region in a movie by calculating the character region and a method of detecting a conflict transition scene from a graph of character region's change. To verify the performance of the proposed method, an experiment was conducted to extract conflict transition scenes for 7 movies, and performance evaluation results of 73.57% accuracy and 77.26% recall were obtained. This proves that it is possible to extract conflict transition scenes based on the character region.

An Improved Method for Detecting Caption in image using DCT-coefficient and Transition-map Analysis (DCT계수와 천이지도 분석을 이용한 개선된 영상 내 자막영역 검출방법)

  • An, Kwon-Jae;Joo, Sung-Il;Kim, Gye-Young;Choi, Hyung-Il
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.4
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    • pp.61-71
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    • 2011
  • In this paper, we proposed the method for detecting text region on image using DCT-coefficient and transition-map analysis. The detecting rate of traditional method for detecting text region using DCT-coefficient analysis is high, but false positive detecting rate also is high and the method using transition-map often reject true text region in step of verification because of sticky threshold. To overcome these problems, we generated PTRmap(Promising Text Region map) through DCT-coefficient analysis and applied PTRmap to method for detecting text region using transition map. As the result, the false positive detecting rate decreased as compared with the method using DCT-coefficient analysis, and the detecting rate increased as compared with the method using transition map.

Analysis of Two-Dimensional Flow Fields in the Multi-Stage Turbomolecular Pump Using the DSMC Method

  • Heo, Joong-Sik;Hwang, Young-Kyu
    • International Journal of Air-Conditioning and Refrigeration
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    • v.9 no.2
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    • pp.8-18
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    • 2001
  • The direct simulation Monte Carlo Method is applied to investigate the two-dimensional flow fields of a turbomolecular pump(TMP) in both molecular and transition flow regions. The pumping characteristics of the TMP are investigated for a wide range of the Knudsen number. The maximum of compression ratio and of pumping speed strongly depend on the Knudsen number in transition region, while they weakly depend on the Knudsen number in free molecular flow region. The present numerical results show good agreement with the previously known experimental data. Finally. the results of the single blade row in both molecular and transition regions are used to predict the overall performance of a TMP, which has three kinds of blade with 24-rows.

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Observation of Transition Boundary between Cold, Dense and Hot, Tenuous Plasmas in the Near-Earth Magnetotail

  • Kim, Hee-Eun;Lee, Ensang
    • Journal of Astronomy and Space Sciences
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    • v.37 no.2
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    • pp.95-104
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    • 2020
  • Properties of plasmas that constitute the plasma sheet in the near-Earth magnetotail vary according to the solar wind conditions and location in the tail. In this case study, we present multi-spacecraft observations by Cluster that show a transition of plasma sheet from cold, dense to hot, tenuous state. The transition was associated with the passage of a spatial boundary that separates the plasma sheet into two regions with cold, dense and hot, tenuous plasmas. Ion phase space distributions show that the cold, dense ions have a Kappa distribution while the hot, tenuous ions have a Maxwellian distribution, implying that they have different origins or are produced by different thermalization processes. The transition boundary separated the plasma sheet in the dawn-dusk direction, and slowly moved toward the dawn flank. The hot, tenuous plasmas filled the central region while the cold, dense plasmas filled the outer region. The hot, tenuous plasmas were moving toward the Earth, pushing the cold, dense plasmas toward the flank. Different types of dynamical processes can be generated in each region, which can affect the development of geomagnetic activities.

소형 펀치 시험에 의한 강용접부의 파괴강도 평가에 관한 연구 1

  • 유대영;정세희;임재규
    • Journal of Welding and Joining
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    • v.7 no.3
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    • pp.28-35
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    • 1989
  • It was reported that the toughness for welded region was influenced by various factors such as the gradient for prior austenite grain size, the variation of microhardness and the characteristic microstructure depending on distance from the fusion boundary. Therefore, in order to evaluate the fracture strength of the weldment in which the microstructures change continuously, it is important to assess the peculiar strength of each microstructure in welded region. It was known that the small punch(SP) test technique which was originally developed to study the irradiation damage effect for the structures of nuclear power plant was also useful to investigate the strength evaluating of nonhomogeneous materials. In this paper, by means of a small punch test technique the possibility of evaluating strength of parent and welded region in SS41 and SM53B steels was investigated. The obtained results are summerized as follows: 1) The small punch test which showed markedly the ductile-brittle transition behavior in this experiment may be applied to evaluation for the fracture strength of welded region. 2) It was shown that the ductile-brittle regime lied in Region III(plastic membrane stretching region) of the flow characteristics observed in SP test. 3) The SP test technique which shows a more precipitous energy change transition behavior than the other test technique is able to estimate the more precise transition temperature. 4) It could be seen that in comparision with the structure of parent the structure of weld HAZ in SS41 steel was improved while it in SM53B steel was deteriorated.

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