• Title/Summary/Keyword: flow localization

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Current Status and Issues in Digital Trade Agreements: Focusing on Cross-border Data Flows and Data Protection (디지털 통상의 국제규범화 현황과 쟁점: 국경 간 데이터 이동 및 데이터 보호를 중심으로)

  • Joo Hyoung Lee;Jeongmeen Suh;Jaeyoun Roh
    • Korea Trade Review
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    • v.46 no.3
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    • pp.99-117
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    • 2021
  • Korea's FTA e-commerce regulations are evolving into a standardized norm. However, "location of computing facilities", which was not covered by Korea's existing FTA, was newly established in Korea's first Mega FTA, RCEP. China, a member of RCEP, restricts data movement and requires data localization through its Cybersecurity law. These facts have led to start this study with interest in data-related regulations. It examined country-specific and regulatory characteristics in the process of forming digital trade norms, using the TAPED established by Burri et al. (2020). It also analyzed the current status of introducing norms related to 'data flow', 'data localization' and 'data protection' of the EU, USA and China, which are leading the formation of e-commerce trade norms. Finally, the legal review was conducted to compare the exact meaning of the wording expressed in each agreement for the six recently enacted Mega FTAs and Digital Economic Agreements. These findings are meaningful in that they provided implications for the effectiveness of RCEP and the direction of negotiations on Korea's digital trade norms.

A Study of Localization for Adiabatic Shear Band in WHA(Tungsten Heavy Alloy) (텅스텐 중합금의 단열전단밴드 형성 및 국부화에 대한 연구)

  • Hwang, Doo-Son;Hong, Sung-In
    • Journal of the Korean Society of Propulsion Engineers
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    • v.11 no.6
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    • pp.18-25
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    • 2007
  • In a plastic metal forming of thermally rate-sensitive material, the localized shear band stems from evolution of a narrow region in which intensive plastic flow occurs. And it give rise to fatal fracture with plastic instability. The objectives of this study are to investigate the localization behavior by using numerical method and predict the failure for WHA(Tungsten Heavy Alloy). In this work, the implicit finite difference scheme is used because of the advantage about convergence and the numerical stability. This study is based on an analysed material with hardening as well as thermally softening behavior which includes isotropic strain hardening and observed the extension of localization within shear band according to material properties.

A Study of Localization for Adiabatic Shear Band Using Non-local Theory (Non-local 이론을 적용한 단열전단밴드의 국부화에 대한 연구)

  • Lee Y. S.;Lee B. S.;Whang D. S.;Yoon S. J.;Hong S. I.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2001.05a
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    • pp.205-208
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    • 2001
  • Localized shear band is investigated through the analysis of one-dimensional model for simple shearing deformation of thermally rate dependent material. Generally mesh size or interval of nodes play an important role in determining the overall flow behavior of the material. In order to observe these size effects we adapted non-local theory by including higher order strain gradients of the equivalent strain into the constitutive equation for the flow stress. for the ease of convergence and numerical stability the inplicit finite difference scheme is employed.

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The dilatancy and numerical simulation of failure behavior of granular materials based on Cosserat model

  • Chu, Xihua;Yu, Cun;Xu, Yuanjie
    • Interaction and multiscale mechanics
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    • v.5 no.2
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    • pp.157-168
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    • 2012
  • The dilatancy of granular materials has significant influence on its mechanical behaviors. The dilation angle is taken as a constant in conventional associated or non-associated flow rules based on Drucker-Prager yields theory. However, various experimental results show the dilatancy changes during progressive failure of granular materials. A non-associated flow rule with evolution of dilation angle is adopted in this study, and Cosserat continuum theory is used to describe the behaviors of granular materials for considering to some extent the its internal structure. Numerical examples focus on the bearing capacity and localization of granular materials, and results illustrate the capability and performance of the presented model in modeling the effect on failure behavior of granular materials.

Evaluation of Geographic Indices Describing Health Care Utilization

  • Kim, Agnus M.;Park, Jong Heon;Kang, Sungchan;Kim, Yoon
    • Journal of Preventive Medicine and Public Health
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    • v.50 no.1
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    • pp.29-37
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    • 2017
  • Objectives: The accurate measurement of geographic patterns of health care utilization is a prerequisite for the study of geographic variations in health care utilization. While several measures have been developed to measure how accurately geographic units reflect the health care utilization patterns of residents, they have been only applied to hospitalization and need further evaluation. This study aimed to evaluate geographic indices describing health care utilization. Methods: We measured the utilization rate and four health care utilization indices (localization index, outflow index, inflow index, and net patient flow) for eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee replacement surgery, caesarean sections, hysterectomy, computed tomography scans, and magnetic resonance imaging scans) according to three levels of geographic units in Korea. Data were obtained from the National Health Insurance database in Korea. We evaluated the associations among the health care utilization indices and the utilization rates. Results: In higher-level geographic units, the localization index tended to be high, while the inflow index and outflow index were lower. The indices showed different patterns depending on the procedure. A strong negative correlation between the localization index and the outflow index was observed for all procedures. Net patient flow showed a moderate positive correlation with the localization index and the inflow index. Conclusions: Health care utilization indices can be used as a proxy to describe the utilization pattern of a procedure in a geographic unit.

Wrinkle Defect of Low Carbon Steel in Wire Rod Rolling (저탄소강 선재 압연의 주름성 결함)

  • Kim H. Y.;Kwon H. C.;Byon S. M.;Park H. D.;Im Y. T.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.08a
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    • pp.307-316
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    • 2004
  • This study examined the cause of the wrinkle defect which is frequently encountered in wire rod rolling of low carbon steel$(C0.08\~0.13wt.\%)$. Even a small defect on the surface of rolled bars can easily develop into fatal cracks during cold heading process of low carbon steel, and it is therefore necessary to minimize inherent defects on the surface of hot rolled bars. Hot rolling process of low carbon steel was analyzed to identify the cause of the wrinkle defect in conjunction with FE analysis. The integrated analysis revealed that the wrinkle defect initiated in the first stage of rolling, and it was at the billet edge where severe deformation and drastic temperature drop were present. To elucidate the micro-mechanical mechanism of the wrinkle defect, hot compression tests were carried out at various temperatures and strain rates using Gleeble-3800. The surface profile of the each other compressed specimens was compared, and rough surface lines were observed at relatively low temperatures. Those surface defects can develop into wrinkles during multi-pass rolling. To control the wrinkle defect in rolling, it is necessary to design an adequate caliber which can minimize the loss of ductility, and thereby prevent flow localization. To use the result of this study fur other steels, the quantitative measure of the wrinkle defect and flow localization parameter should be proposed.

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A Study of Localization with Material Properties Using Numerical Method (재료의 특징에 따른 국부화에 대한 수치해석적 연구)

  • 황두순;이병섭;이용성;윤수진;홍성인
    • Transactions of Materials Processing
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    • v.9 no.4
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    • pp.395-403
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    • 2000
  • Formation of Shear Band under the adiabatic condition is widely observed In the engineering materials during rapidly forming process lot a thermally rate-dependent material. The shear band stems from evolution of a narrow region in which an intensive plastic flow occurs. The shear band often plays a role of a precursor of the ductile fracture during a forming process. The objective of this study is to investigate the localization behavior using numerical method. In this work, the implicit finite difference scheme is employed due to the ease of convergence and the numerical stability It is noted that physical and mechanical properties of materials determine how the shear band is formed and then localized. Material properties can be characterized with inertia number dissipation number and diffusion number. It is observed that the dimensionless numbers effect on localization. Using a parametric study, comparison was made between CRS-1018 steel with WHA (tungsten heavy alloy). The deformation behavior of material in this study include an isotropic hardening as well as thermal softening. Moreover, this study suggests that a kinematic hardening constitutive relation be required to predict a more accurate strain level at a shear band.

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Experimental Localization of flow Limiting Segment (Flow limitation이 일어나는 기도내 위치의 실험적 측정)

  • 차은종;이태수
    • Journal of Biomedical Engineering Research
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    • v.13 no.3
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    • pp.209-216
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    • 1992
  • A new experimental technique is proposed to localize the flow limiting segment(FLS) during forced expiration. The present technique is based on the pressure drip across FLS and a consequent change in airway resistance, which can provide an accurate and objective location of FLS. During forced expiratory maneuver artificially induced by a strong negative pressure (-100mmHg) applied at the trachea in an anesthetized open chest dog, airway resistance( R) was calculated from air flow and airway pres- sure signals at various airway locations and lung volumes, At the lung volumes above 10 % VC, FLS located in the trachea 6cm lower from the larynx. With the lung volume decreased below 8% VC, FLS jumped upstream to End-3rd generation of the airway. These results were similar with the previous reports from excised dog lungs, which demonstrated the validity of the present technique. Since the present technique provides a more objective measure of FLS location, it would be useful in future studies of expiratory flow limitation.

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Blood Flow in an Aortic Bifurcation Model: Pulsed Doppler Ultrasound and Laser Doppler Anemometry Studies (대동맥분기에서의 혈액유동: 맥도플러초음파 및 레이저도플러계측기를 사용한 연구)

  • Kim, Young-H.
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.11
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    • pp.43-46
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    • 1992
  • $\underline{In\;vitro}$ velocity measurements were made using both the pulsed Doppler ultrasound (PDU) machine and laser Doppler anemometer (LDA) system in order to investigate the flow characteristics near the aortic bifurcation. Velocities measured from the PDU machine was in good agreement with those from the LDA. The flow in the daughter branches was three-dimensional with a secondary flow. The oscillating wall shear stress with this secondary fluid motion is well correlated with the localization of the atherosclerosis.

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