• Title/Summary/Keyword: residual time

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Effects of Residual Stress and Surface Defect on the Mechanical Properties of the High Carbon Steel Filaments (고 탄소 미세 강선의 기계적 특성에 미치는 잔류 응력과 표면 결함의 영향)

  • Yang, Y.S.;Bae, J.G.;Park, C.G.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.10a
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    • pp.134-137
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    • 2008
  • The effects of residual stress and surface defects on the mechanical properties of the high carbon steel filament used for the automotive tire have been experimentally investigated. The samples were fabricated with annealing temperature. The residual stress was measured by focused ion beam and strain mapping software which has advantages, such as data with high accuracy and fast data acquisition time. Mechanical properties, such as tensile strength and fatigue resistance, were gradually increased up to $200^{\circ}C$ and then slightly decreased. From the measurement of residual stress and level of surface defect, it was revealed that the critical factor was varied with different temperature region. That is, the fatigue resistance increased due to decreasing the residual stress and decreased due to increasing the size and distribution of surface defect.

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Effects of Residual Phosphorus Content on color Reversion and Storage Stability of Corn Germ Oil (잔류 인함량이 옥배유의 변색및 저장안정성에 미치는 영향)

  • 김종승;이근보;이미숙
    • Journal of Food Hygiene and Safety
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    • v.12 no.2
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    • pp.107-110
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    • 1997
  • To examine the effects of residual phosphorus content on color reversion and storage stability of corn germ oil, the changes of Lovibond total color and stability of oxidation were determined according to the different storage periods at room and incubating temperature, respectively. The residual phosphorus content and storage temperature had the synergistic effect on color reversion during short time storage. The extent of color change was the greatest when oils were stored for 1.0∼1.5 years at room temperature and thereafter gradually tended to reverse color reversion. It is supposed that the double bonds of carotenoids in oils were oxidized and then turned to the volatiles such as epoxide, ionone, and etc. In contrast, the residual phosphorus content increased oxidation stability of oils. The residual phosphorus content was closely correlated with the color reversion and storage stability, respectively.

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A Study on the Stabilization of Gun Barrel by Viscoelastic Damping Material (점탄성 감쇠재료를 이용한 포신 잔류진동의 조기 안정화 방안연구)

  • 임재희;백판구;이재영;정백기
    • Journal of KSNVE
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    • v.9 no.4
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    • pp.714-719
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    • 1999
  • Because the residual vibration of a gun barrel acts negatively on the firing of a large calibers gun, the fast stabilization of theresidual vibration is indispensible to the precise and successive firing. In this study, the residual vibrations of a gun barrel carrying a bore evacuator and a muzzle brake are investigated by the experimental method. The influence of the eigenfrequencies and the mode shapes of gun barrel on the fast stabilization of the residual vibration is studied for the various masses of bore evacuator and muzzle brake, the possition of bore evacutor. Also the relationships between the funcamental frequencies and the settling times of the gun barrel are investigated for the various parameters. The experiments to reduce the residual vibration using the viscoelastic damping treatment gives the best result among the various treatments for the reduction of residual vibration of the system.

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The Effects of the Drive-in Process Parameters on the Residual Stress Profile of the p+ Thin Film (후확산 공정 조건이 p+ 박막의 간류 응력 분포에 미치는 영향)

  • Park, T.G.;Jeong, O.C.;Yang, S.S.
    • Proceedings of the KIEE Conference
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    • 1998.11c
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    • pp.1007-1009
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    • 1998
  • In this paper, the effects of the drive-in process parameters on the residual stress profile of the p+ silicon film has been investigated. All the residual stress profile has been estimated by the second-order polynomial. All the coefficients of the polynomial have been determined from the measurement of the deflections of cantilevers and a rotating beam by using a surface profiler meter and by means of focusing a calibrated microscope. As the drive-in temperature or the drive-in time increases, the boron concentration decreases and the magnitude of the average residual stress decreases. If the boron concentration decreases the tensile residual stress decreases except near the surface where the magnitude of compressive residual stress increases.

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A Study on the Development of Stress Optic Law Considering Residual Stress in Photoelastic Experiment(II) -Application of Stress Optic Law Considering of Residual Sterss- (잔류응력을 고려한 광탄성실험의 광응력법칙 개발에 관한 연구 (2) -잔류응력을 고려한 광응력법칙의 응용-)

  • 서재국;황재석;최선호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.8
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    • pp.1810-1821
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    • 1995
  • Photoelastic experiment has been used to analyze stress of structure and stress in the vicinity of crack tip etc.. Model experiment such as photoelastic experiment has been restricted by problem of residual stress in the photoelastic model material. They are generated by molding, cutting and time effects etc.. They produce some errors in the results of photoelastic experiment data. In this paper, stress optic law considering residual stress already developed by authors was applied to the stress concentration problem and fracture mechanics. Although the specimen was bad with residual stress, we could obtain good results by using the stress optic law considering residual stress. It was found that the stress optic law of photoelastic experiment could be applied to the stress analysis of bimaterial.

Thermo-Viscoelastic Residual Stress Analysis of Metal Liner-Inserted Composite Cylinders

  • Hwang, Ho-Yon;Kim, Yeong-Kook;Kim, Cheol;Kwon, Young-Doo;Park, Woong
    • Journal of Mechanical Science and Technology
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    • v.17 no.2
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    • pp.171-180
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    • 2003
  • One of the most significant problems in the processing of composite materials is residual stress. The high residual stress may cause cracking in the matrix without external loads and degrade the integrity of composite structures. In this study, thermo-viscoelastic residual stresses occurred in an aluminum liner-inserted polymer composite cylinder are investigated. This type of the structure is used for rocket fuselage due to the convenience to attach payloads and equipment to the metal liner by machining. The time and degree of cure dependent thermo-viscoelastic constitutive equations are developed and coupled with a thermo-chemical process model. These equations are solved with the finite element method to predict the residual stresses in the composite cylinder and also in the interface between the liner and the composite during cure.

광도만에 있어서 물질수송과정의 수치예측

  • 이인철;류청로
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.10a
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    • pp.159-164
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    • 2000
  • In order to clarify the seasonal variation of residual current and material transportation process in Hiroshima Bay, JAPAN, the real-time simulation of residual current and particle tracking by using Euler-Lagrange model were carried out. The calculated tidal current and water temperature and salinity showed good agreement with the observed ones. The residual currents showed the southward flow pattern at the upper layer, and the northward flow pattern at the lower layer. The flow structure of residual current in Hiroshima Bay is an estuarine circulation affected by density flow and wind driven current. The residual current plays an improtant role of material transportation in th bay.

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A Study on Low Power Algorithm for Battery residual capacity and a Task (배터리 잔량과 태스크에 따른 저전력 알고리즘 연구)

  • Kim, Jae Jin
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.1
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    • pp.53-58
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    • 2013
  • In this paper, we proposed low power algorithm for battery residual capacity and a task. Algorithm the mobile devices power of the battery residual capacity for the task to perform power consumption to reduce the frequency alters. Task is different in power consumption according to kinds of in time accomplishment device to use. Adjustment of power consumption analyzes kinds of given tasks from having the minimum power consumption task to having the maximum power consumption task. Control frequency so that power consumption waste to be exposed to battery residual capacity can be happened according to the results analyzed. Experiment the frequency by adjusting power consumption a method to reduce using [7] and in the same environment power of the battery residual capacity consider the task to perform frequency were controlled. Efficiency was proved compare with the experiment results [7]. The experiments results show increment in the number of processing by 45.46% comparing with that [7] algorithm.

Residual displacement estimation of simple structures considering soil structure interaction

  • Aydemir, Muberra Eser;Aydemir, Cem
    • Earthquakes and Structures
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    • v.16 no.1
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    • pp.69-82
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    • 2019
  • As the residual displacement and/or drift demands are commonly used for seismic assessment of buildings, the estimation of these values play a very critical role through earthquake design philosophy. The residual displacement estimation of fixed base structures has been the topic of numerous researches up to now, but the effect of soil flexibility is almost always omitted. In this study, residual displacement demands are investigated for SDOF systems with period range of 0.1-3.0 s for near-field and far-field ground motions for both fixed and interacting cases. The elastoplastic model is used to represent non-degrading structures. Based on time history analyses, a new simple yet effective equation is proposed for residual displacement demand of any system whether fixed base or interacting as a function of structural period, lateral strength ratio and spectral displacement.

Calculation of residual stresses by thermal elasto-plastic analysis (열탄소성 해석에 의한 잔류응력의 계산)

  • 장창두;서승일
    • Journal of Welding and Joining
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    • v.6 no.4
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    • pp.35-43
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    • 1988
  • Welding residual stresses were calculated by two dimensional thermal elasto-plastic analysis using element method. Complicated plastic behavior during heat transfer was simulated with time. Fist, temperature distributions. To consider time varying behavior of material properties and loading and unloading processes, iterative calculation based on initial stiffness method was carried out. The method proposed by Yamata was used in time increment control which determined the accuracy of claculation. comparison with other caculated and experimental results shows fairly good agreement.

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