• Title/Summary/Keyword: restraining

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Microstructure and Mechanical Property of Brazed Joint in Duplex Stainless Steel, UNS32550 (브레이징한 2상 스테인리스강 UNS32550의 미세조직 및 기계적 특성)

  • 김대업;강정윤
    • Journal of Welding and Joining
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    • v.21 no.2
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    • pp.64-69
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    • 2003
  • The bonding phenomena and mechanical property of duplex stainless steel during brazing have been investigated. The UNS32550 was used for base metal, and the MBF50 was used for insert metal. Brazing was carried out under the various conditions (brazing temperature : 1473K, 1498K, holding time : 0∼1.8ks). There were various microconstituents in the bonded interlayer because of reaction between liquid insert metal and base metal. In the early stage of brazing, BN is formed in the bonded interlayer and base metal near the bonded layer. Cr made is formed in the bonded interlayer. The amount of BN and Cr nitrides decrease with the increase of bonding temperature and holding time. Superior shear strength of 550MPa is obtained by restraining the formation of nitrides. (Received January 17, 2003)

Three-dimensional Analysis for Solidification and Bulging of Continuously Cast (연속 주조의 응고와 벌징에 관한 3차원 해석)

  • Kim Y. D.;Cho J. R.;Lee B. Y.;Ha M. Y.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2000.10a
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    • pp.174-177
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    • 2000
  • In this paper, The bulging behavior of the solidified shell in continuously cast slabs have been numerically analyzed using three-dimensional elasto-plastic and creep finite element method Three-dimensional model has been applied in order to investigate the effect of the narrow face shell on restraining the bulging deflection. Solidification analysis are carried out by two-dimensional finite difference method. In this way, strains occurring at the solidification front near the narrow face of the slab, as well as those occurring in the board face have been computed. The adequacy of the model has been checked against the experimental results. In addition, the effect of the slab width and casting speed on the bulging are discussed.

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Guidelines for Happiness : Lessons from the Cases in the 'Happy Family Story Contest' (행복감을 주는 삶의 지침 연구 -우리가정 행복나누기 공모사례분석을 통하여)

  • Lee Young-Ho;Chi Young-Sook;Choi Bo-A
    • Journal of Families and Better Life
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    • v.23 no.1 s.73
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    • pp.41-51
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    • 2005
  • At this time when the Healthy Family Act has become effective, promoting popular consciousness on a happy family life and providing guidelines to happiness are important. This study analyzed the content of 250 cases that entered the 'Happy Family Story Contest' in order to extract some common qualifies of happy families. As a result, nine characteristics were found: 1) a sense of achievement in having made a happy family 2) a sense of togetherness and solidarity 3) self-discipline 4) a Positive relationship with others 5) accomplishing one small step at one time 6) autonomy and candid communication 7) overcoming crises 8) cherishing what one has in the present 9) restraining greed and letting go. The findings of this study will help individuals reorient their lives as well as inspire the professionals to develop programs.

Pushover Analysis Considering Effects of Degradation of Shear Strength (전단강도 감소효과를 고려한 Pushover 해석)

  • Lee, Young-Wook
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05a
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    • pp.514-517
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    • 2006
  • Nonseismic designed RC frame have a possibility of shear failure because of deficiencies of reinforcing details. To model the shear failure in numerical analysis, shear strength degradation models which include Moehle's and ATC 40 are compared and applied to push-over analysis. For numerical analysis, three storied building frame is selected and designed according to Korean Concrete Design Code(2003). From the numerical analysis, it is pointed out that there may be great difference in lateral drift capacity if a different shear strength model is used. And the capacity can be severely underestimated if the restraining model of plastic rotation of ATC 40 is used, compared to the use of shear spring for shear degradation.

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Stationary position control of a wheeled blimp

  • Mihee Nam;Sungchul Kang;Yoon, Seong-sik;Takashi Tsubouchi
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.117.4-117
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    • 2002
  • This paper describes a stationary position control of a wheeled blimp. The wheeled blimp is composed of a blimp filled with helium gas and a wheeled vehicle part. The wheeled blimp is designed to enable both flying in the air and standing on the floor. The wheeled blimp stands on the floor keeping its balance. However, it is difficult for the wheeled blimp to maintain a stationary position in standing phase since the stationary blimp system responds sensitively to air current even in indoor environments. In order to keep the stationary position restraining motion caused by an uncertain airflow, a position controller for the wheeled blimp is needed. Controller design based on dynamic m...

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A Study on Control of the Thermal Expansion for Ball Screw of CNC Machin Tools (CNC 공작기계용 볼스크류의 열팽창 억제에 관한 연구)

  • 전언찬
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.7 no.4
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    • pp.73-78
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    • 1998
  • In this paper, we have studied about the thermal expansion of the ball screw used for the CNC machine tools. The hollow ball type is used for the ball screw. We have compared the conventional cooling system and function with the improved cooling system and function which is developed the path providing cooling oil in hollow ball screw. That is the temperature variation and positioning accuracy are analyzed of the ball screw. We have obtained the following results through this experiment. 1) The improved cooling system of the hollow ball screw for CNC machine tools was developed 2) The improved cooling system of the hollow ball screw has a large effectiveness on restraining the thermal expansion of the ball screw. 3) The positioning accuracy of the ball screw was improved about 2~4$\mu$m using temperature -controlled cooling oil.

An investigation into structural behaviour of modular steel scaffolds

  • Yu, W.K.
    • Steel and Composite Structures
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    • v.4 no.3
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    • pp.211-226
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    • 2004
  • This paper presents a study on the structural behaviour of modular steel scaffolds through both experimental and numerical investigations. Three one-storey and three two-storey modular steel scaffolds were built and tested to failure in order to examine the structural behaviour of typical modular steel scaffolds. Details of the tests and their test results were presented in this paper. Moreover, an advanced non-linear analysis method was employed to evaluate the load carrying capacities of these scaffolds under different support conditions. Comparisons between the experimental and the numerical results on the structural behaviour of these modular steel scaffolds were also presented. Moreover, the restraining effects of external supports in practical situations were also studied through finite element methods. The predicted load carrying capacities and deformations at failure of these models under partially restrained conditions were found to be close to the experimental results. A codified design method for column buckling with modified slenderness ratios was adopted for practical design of modular steel scaffolds.

Numerical Modeling of Soil-Reinforcement Interaction Under a Buried Pipeline (매설관 하부지반-보강재 상호작용의 수치모델 연구)

  • 손준익;정하익
    • Computational Structural Engineering
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    • v.4 no.3
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    • pp.129-135
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    • 1991
  • This paper reports the application study of the ground reinforcement under a buried pipeline subjected to differential settlement via a finite element modeling. The soil-reinforcement interaction helps to minimize the differential settlement between the adjoining pipe segments. The settlement pattern and deformation slope of a pipeline have been evaluated for a boundary condition at the joint between a rigid structure and a pipeline. The analysis results are compared for both non-reinforced and reinforced cases to numerically evaluate the stress transfer mechanism and the effectiveness of the soil reinforcement for restraining the settlement of the pipeline.

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An Experimental Study on the Effects of Sineungyangjin-Dan Applied to the Treatment of Alopecia (脫毛에 應用되는 神應養眞丹의 效能에 關한 實驗的 硏究)

  • Kim, So-Yeong;Kim, Jung-Ho;Chae, Byeong-Yun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.4 no.1
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    • pp.43-58
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    • 1991
  • In order to verify the effect of Sineungyangjin-Dan on alopecia, I experimented the hair regrowth of the normal mice and of the high butter diet-pretreated mice by feeding each group of mice a certain amount of ethanol extract of Sineungyangjin-Dan and water extract and thus obtained the results as follow; 1. The ethanol extract of Sineungyangjin-Dan was proved to promote the hair regrowth of the hair-removed normal mice. 2. 360mg/kg ethanol extract of Sineungyangjin-Dan was proved to have the effect of promoting hair regrowth by restraining the increase of free cholesterol and triglyceride but by helping the increase of free fatty acid in skin. As a result of the above study Sineungyangjin-Dan was proved to have the effect of promoting hair regrowth.

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Development of Drawbead Expert Models for Finite Element Analysis of Sheet Metal Forming Process (Part2: Modeling) (박판성형공정의 유한요소해석을 위한 드로우비드 전문모델 개발 (2부:모델링))

  • 금영탁;이재우;박승우
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1997.03a
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    • pp.50-54
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    • 1997
  • An expert drawbead model is developed to model a cranky drawbead in the finite element analysis of stamping processes. The expert model calculates the drawbead restraining forces (DBRF's) and bead-exit thinning, which are boundary conditions. DBRF's are calculated by considering bending force, unbending force, and friction force in order. Bead-exit thinning are due to the bending and tension during the deformation. The DBFR's and thinning computed form the mathematical model for the basic beads are compared with measurements and correction factors compensating for the differences are found using the multiple linear regression method. The composition beads are assumed to be a combination of basic beads so that the DBRF's and bead-exit thinning are computed to the sum of those of basic beads.

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