• Title/Summary/Keyword: Bulging Process

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Load Sharing Control of Driven Roll in Continuous Caster (연속주조기에서 스트랜드 구동롤의 인발력 분배 제어)

  • 천창근;김철우
    • The Transactions of the Korean Institute of Power Electronics
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    • v.8 no.4
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    • pp.321-327
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    • 2003
  • As the continuous casting process is to product slab with high temperature liquid steel, the main role of strand driven roll is to withdraw slab from mold as operator set up casting speed pattern. The strand driven roll in old cast machine is controlled casting speed only. Due to inaccuracies in drive setting up, varying roll diameters, bulging in the product, withdrawal force was distributed irregularly. As a result, because of horizontal crack in slab comer, high casting speed can't be achieved. In this paper, the correlation between the distribution of withdrawal force and slab quality is investigated and the new control algorithm which can be distributed regularly the withdrawal force of strand driven roll is proposed. The principle of proposed algorithm is not to control motor torque directly but to control motor speed reference according to sharing ratio of withdrawal force which is set up in high level controller. The proposed algorithm implemented in POSCO Kwangyang 1-4 continuous casting plant.

Safety assessment of generation III nuclear power plant buildings subjected to commercial aircraft crash part III: Engine missile impacting SC plate

  • Xu, Z.Y.;Wu, H.;Liu, X.;Qu, Y.G.;Li, Z.C.;Fang, Q.
    • Nuclear Engineering and Technology
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    • v.52 no.2
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    • pp.417-428
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    • 2020
  • Investigations of the commercial aircraft impact effect on nuclear island infrastructures have been drawing extensive attention, and this paper aims to perform the safety assessment of Generation III nuclear power plant (NPP) buildings subjected to typical commercial aircrafts crash. At present Part III, the local damage of the rigid components of aircraft, e.g., engine and landing gear, impacting the steel concrete (SC) structures of NPP containment is mainly discussed. Two typical SC target panels with the thicknesses of 40 mm and 100 mm, as well as the steel cylindrical projectile with a mass of 2.15 kg and a diameter of 80 mm are fabricated. By using a large-caliber air gas gun, both the projectile penetration and perforation test are conducted, in which the striking velocities were ranged from 96 m/s to 157 m/s. The bulging velocity and the maximal deflection of rear steel plate, as well as penetration depth of projectile are derived, and the local deformation and failure modes of SC panels are assessed experimentally. Then, the commercial finite element program LS-DYNA is utilized to perform the numerical simulations, by comparisons with the experimental and simulated projectile impact process and SC panel damage, the numerical algorithm, constitutive models and the corresponding parameters are verified. The present work can provide helpful references for the evaluation of the local impact resistance of NPP buildings against the aircraft engine.

Analysis of the Axisymmetric Hydro-Mechanical Deep Drawing Process by Using the Finite Element Method (유한 요소법을 이용한 축대칭 하이드로 미케니칼 디프 드로잉 공정의 해석)

  • 양동열;김한경;이항수;김경웅
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.5
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    • pp.873-882
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    • 1992
  • The study is concerned with the rigid-plastic element analysis for axisymmetric hydromechanical deep drawing in which the fluid flow influences the metal deformation. Due to the fluid pressure acting on the sheet material hydromechanical deep drawing is distinguished from the conventional deep drawing processes. In considering the pressure effect, the governing equation for fluid pressure is solved and the result is reflected on the global stiffness matrix. The solution procedure consists of two stages ; i.e., initial bulging of the sheet surface before the initiation of steady fluid flow in the flange and fluid-lubricated stage. The problem is decoupled between fluid analysis and analysis of solid deformation by deformation by iterative feedback of mutual computed results. The corresponding experiments are carried out for axisymmetric hydro-mechanical deep drawing of annealled aluminium sheet as well as for deep drawing. It has been shown from the experiments that the limit drawing ratio for hydro-mechanical deep drawing is improved as compared with deep drawing. The computed results are in good agreement with the experiment for variation of punch head and chamber pressure with respect to the punch travel and for distribution of thicknees strain. It is thus shown that the present method of analysis can be effectively applied to the analysis of axisymmetric hydro-mechanical deep drawing processes.

A Study on Fusionization of Woman Characters in Fusion Traditional Drama (사극드라마의 여자캐릭터의 분장특성 연구)

  • Kim, Yu-Gyoung;Cho, Ji-Na
    • Journal of Fashion Business
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    • v.13 no.4
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    • pp.60-76
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    • 2009
  • Expression of woman characters in fusion traditional dramas plays a role of making the progress of dramas not bigoted and new. Especially, woman characters have a high weight as a heroine by an increase in their image in fusion traditional dramas. Expression of characters harmonizing modern with tradition has also given a help in reflecting a trend of the present times. Hair style and face makeup of woman characters in fusion traditional dramas are in the process of fusionization getting an effect from postmodernism. They are expressing the hair style of symbolization modern elements of hair style to traditional hair styles. They also expressed a neutral image with faded hair styles in the shaggy cut style and dye of neoplaticism. Neo-hippie style was changed into the style of naturalism and nationalism and the hair style braided in various branches as the one of Indians was changed into a primitive and national feature. It is producing a new style by permitting even a long-hair permanent wave hair style. Expression of straight hair style, a long-hair shaggy & bulging wave style and a hair style of neoplaticism, was distinguished. In the side of face makeup, they expressed its luxurious and splendid style by attaching great importance to its luster and are exposing images of characters by a smoky makeup emphasizing eye lines. Their face makeup was almost never separated from present dramas as using pearl shadow in a glossy lips makeup and color, which made it possible to express it more dramatically in fusion traditional dramas than in present dramas. In the event of the makeup element of fusion traditional dramas permitting diversity, the character makeup of fusion traditional dramas made a foundation to show people diverse elements of makeup by mix & match a present elements and past elements of historical research, which made it possible to express a unique makeup or a special makeup. Diverse makeup expressions were limited by reflection of illumination even in the existing videos. Therefore, 'Fusion' made it possible to express it more freely in fusion traditional dramas than in present dramas.

Mechanical behaviour of composite columns composed of RAC-filled square steel tube and profile steel under eccentric compression loads

  • Ma, Hui;Xi, Jiacheng;Zhao, Yaoli;Dong, Jikun
    • Steel and Composite Structures
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    • v.38 no.1
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    • pp.103-120
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    • 2021
  • This research examines the eccentric compression performance of composite columns composed of recycled aggregate concrete (RAC)-filled square steel tube and profile steel. A total of 17 specimens on the composite columns with different recycled coarse aggregate (RCA) replacement percentage, RAC strength, width to thickness ratio of square steel tube, profile steel ratio, eccentricity and slenderness ratio were subjected to eccentric compression tests. The failure process and characteristic of specimens under eccentric compression loading were observed in detail. The load-lateral deflection curves, load-train curves and strain distribution on the cross section of the composite columns were also obtained and described on the basis of test data. Results corroborate that the failure characteristics and modes of the specimens with different design parameters were basically similar under eccentric compression loads. The compression side of square steel tube yields first, followed by the compression side of profile steel. Finally, the RAC in the columns was crushed and the apparent local bulging of square steel tube was also observed, which meant that the composite column was damaged and failed. The composite columns under eccentric compression loading suffered from typical bending failure. Moreover, the eccentric bearing capacity and deformation of the specimens decreased as the RCA replacement percentage and width to thickness ratio of square steel tube increased, respectively. Slenderness ratio and eccentricity had a significantly adverse effect on the eccentric compression performance of composite columns. But overall, the composite columns generally had high-bearing capacity and good deformation. Meanwhile, the mechanism of the composite columns under eccentric compression loads was also analysed in detail, and the calculation formulas on the eccentric compression capacity of composite columns were proposed via the limit equilibrium analysis method. The calculation results of the eccentric compression capacity of columns are consistent with the test results, which verify the validity of the formulas, and the conclusions can serve as references for the engineering application of this kind of composite columns.

Ultrastructural Alterations in the Gastric Mucous Epithelial Cells of Mouse Inoculated with Ehrlich Carcinoma Cells, Induced by 5-Fluorouracil, Mitomycin C or Acriflavine-Guanosine Compound (AG60) (5-Fluorouracil, Mitomycin C 및 Acriflavine-Guanosine 복합제가 Ehrlich 암세포를 이식한 생쥐 위점막 점액상피세포의 미세구조에 미치는 영향)

  • Ko, Eun-Ju;Park, Kyung-Ho;Park, Dae-Kyoon;Kim, Duk-Soo;Ko, Jeong-Sik
    • Applied Microscopy
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    • v.41 no.1
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    • pp.1-11
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    • 2011
  • This experiment was performed to evaluate the morphological responses of the gastric epithelial cells of the mouse, inoculated with Ehrlich carcinoma cells in the inguinal area, following administration of 5-fluorouracil, mitomycin C or Acriflavine-Guanosine compound (AG60). In this study, each mouse was inoculated with $1{\times}10^7$ Ehrlich carcinoma cells subcutaneously in the inguinal area. From next day after inoculations, 0.2 mL of saline, 5-fluorouracil (30 mg/kg), mitomycin C ($400{\mu}g/kg$) or AG60 (30 mg/kg) were injected to the animals every other day, respectively. Each animals were sacrificed after 7th injection and tissue were taken from the gastric mucosa. Thereafter, the ultrathin sections were stained with uranyl acetate and lead citrate. In the 5-fluorouracil-, mitomycin C- or AG60-treated mice, myelin figures and multivesicular bodies within the gastric mucous epithelial cells were observed more frequently than those of the normal control. In the 5-fluorouracil-treated mice, membrane structures containing a few mucous granules in the luminal space were observed. Indeed, bulging cytoplasmic process containing mucous granules protruding into the gastric lumen were observed in the mitomycin Ctreated mice. Therefore, this study suggested that AG60 as compared with 5-fluorourail and mitomycin C may effective medicine without damage to the secretion ability of gastric mucous epithelial cells.