• Title/Summary/Keyword: homogenous

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Numerical Simulation of the Elastic Moduli of Cement Paste As a Three Dimensional Unit Cell

  • Park, Ki-Bong
    • Architectural research
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    • v.12 no.2
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    • pp.93-98
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    • 2010
  • This paper describes a numerical method for estimating the elastic moduli of cement paste. The cement paste is modeled as a unit cell which consists of three components: the unhydrated cement grain, the gel, and the capillary pore. In the unit cell, the volume fractions of the constituents are quantified using a single kinetic function calculating the degree of hydration. The elastic moduli of cement paste are calculated from the total displacements of constituents when a uniform pressure is applied to the gel contact area. The cement paste is assumed to be a homogenous isotropic matrix. Numerical simulations were conducted through the finite element analysis of the three-dimensional periodic unit cell. The model predictions are compared with experimental results. The predicted trends are in good agreement with experimental observations. This approach and some of the results might also be relevant for other technical applications.

Self-Assembling Adhesive Bonding by Using Fusible Alloy Paste for Microelectronics Packaging

  • Yasuda, Kiyokazu
    • Journal of the Microelectronics and Packaging Society
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    • v.18 no.3
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    • pp.53-57
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    • 2011
  • In the modern packaging technologies highly condensed metal interconnects are typically formed by highcost processes. These methods inevitably require the precise controls of mutually dependant process parameters, which usually cause the difficulty of the change in the layout design for interconnects of chip to-chip, or chip-to-substrate. In order to overcome these problems, the unique concept and methodology of self-assembly even in micro-meter scale were developed. In this report we focus on the factors which influenced the self-formed bumps by analyzing the phenomenon experimentally. In case of RMA flux, homogenous pattern was obtained in both plain surface and cross-section surface observation. By using RA flux, the phenomena were accelerated although the self-formtion results was inhomogenous. With ussage of moderate RA flux, reaction rate of the self-formation was accelerated with homogeneous pattern.

Cross-Cultural Difference between Female Young Adults in Korea and Indonesia in Perceiving Hijabis in the Media

  • Sintowoko, Dyah Ayu Wiwid;Lee, Yoon;Lee, Hye Eun
    • International Journal of Internet, Broadcasting and Communication
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    • v.12 no.3
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    • pp.177-188
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    • 2020
  • The Muslim population is growing significantly in Asian countries. By conducting an experiment, this study examines the cultural differences between South Korean and Indonesian female, young adults, and their perception of hijabis who are represented in the media. The main goal of this study is to compare the perception towards hijabis in a homogenous country new to Muslims against a Muslim-majority country. Results showed that non-hijabis were deemed more physically attractive, empathetic, and enjoyable among Koreans when compared to Indonesians. Through this study, we provide a theoretical explanation using cultivation theory and (parasocial) contact hypothesisto clarify the differences between South Korea and Indonesia. Thisstudy provides a baseline of understanding to determine where both cultures are at in perceiving hijabis. Our results suggest that it will be compelling to correct media representation in order to reduce stereotypes and lead to a successful understanding of both cultures.

1D contaminant transport using element free Galerkin method with irregular nodes

  • Rupali, S.;Sawant, Vishwas A.
    • Coupled systems mechanics
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    • v.5 no.3
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    • pp.203-221
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    • 2016
  • The present study deals with the numerical modelling for the one dimensional contaminant transport through saturated homogeneous and stratified porous media using meshfree method. A numerical algorithm based on element free Galerkin method is developed. A one dimensional form of the advectivediffusive transport equation for homogeneous and stratified soil is considered for the analysis using irregular nodes. A Fortran program is developed to obtain numerical solution and the results are validated with the available results in the literature. A detailed parametric study is conducted to examine the effect of certain key parameters. Effect of change of dispersion, velocity, porosity, distribution coefficient and thickness of layer is studied on the concentration of the contaminant.

Novel Alignment Layers for Ion Beam Method and the Orientations of Liquid Crystal

  • Ahn, Han-Jin;Kim, Kyung-Chan;Kim, Jong-Bok;Baik, Hong-Koo;Park, Chang-Joon;Hwang, Jeoung-Yeon;Seo, Dae-Shik
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.1155-1158
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    • 2004
  • Various inorganic alignment layers of nematic liquid crystal (NLC) molecules were investigated. Ar ion beam (IB) irradiation was utilized for alignment method and homogenous and homeotropic orientations with tilt angle were obtained on the suitable inorganic thin films. Proper doping materials were added to diamond-like carbon (DLC) films. In the case of homogeneous alignment, nitrogen doping affected the increase of pretilt angle, while the fluorine bonding in the DLC films was induced the tilted homeotropic alignment cause its extreme hydrophobic property. These results showed that ion beam irradiation method could be applied to the various alignment mode of NLC such as IPS, TN and MVA.

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The Value of High Resolution Ultrasonography in Diagnosis of Thyroid Nodule (갑상선 결절의 진단에 있어서 고해상능 초음파검사의 가치)

  • Shim Hyung-Jin;Choung Hue-Moon;Yoon Jung-Han;JeGal Young-Jong;Park Jin-Gyoon
    • Korean Journal of Head & Neck Oncology
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    • v.6 no.2
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    • pp.114-118
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    • 1990
  • A clinical study of 37 cases with thyroid nodules, which were treated by surgical excision and confirmed pathologically at the Department of Surgery, Chonnam National University Medical School, from Dec. 1988 to Feb. 1990, was conducted and following results were obtained in ultrasonographic evaluation of thyroid nodules. 1) The thyroid adenoma were showed well-defined margin, homogenous internal echo and surrounding Halo, but thyroid cancer were showed ill-defined margin, inhomogenous internal echo and no surrounding Halo. 2) The sensitivity of high resoution ultrasonography compared with pathologic diagnosis to thyroid cancer was 87.5%, specificity 94.1%, accuracy 88%, false positive 5.88%, and negative 12.5%.

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Synthesis of $Ba(Mg_{1/3}Ta_{2/3})O_3$ Nanopowders by Glycothermal Process

  • Badrakh, Amar;Cho, Hong-Chan;Lim, Dae-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.167-168
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    • 2009
  • Phase pure barium magnesium tantalate $Ba(Mg_{1/3}Ta_{2/3})O_3$(BMT) nanopowders were synthesized at temperature as low as $220^{\circ}C$ through glycothermal reaction by using $Ba(OH)_2{\cdot}8H_2O$, $Mg(NO_3){\cdot}6H_2O$, and $TaCl_5$ as precursors and 1,4-butandiol as solvent. XRD, SEM, and TGA data support that glycothermal processing method provides a simple low temperature route for producing fine grained BMT nanopowders without alkaline mineralizers. BMT nanopowders synthesized at $220^{\circ}C$ showed more homogenous with rounded morphologies.

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Ultrasonographic Changes of Acute Renal Failure Induced by Gentamicin in Dogs (개에서 겐타마이신으로 유발된 급성 신부전의 초음파상 변화)

  • 진경훈;정종태
    • Journal of Veterinary Clinics
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    • v.18 no.1
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    • pp.35-43
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    • 2001
  • Present study was undertaken in order to document early renal ultrasonographic changes of gentamicin nephrotoxicosis and to show the value of renal ultrasonography as a contributory means of early diagnosis of acute renal failure in dogs. The experimental design was a randomized complete block design with six treatments in two blocks (gentamicin-treated & saline-treated). Acute renal failure was induced by toxic dosage of gentamicin (30 mg/kg) and saline solution sham equivalent in volume to that of the toxic dosage of gentamicin (1.5-3ml). Subjective visualization of increased renal cortex was visible as homogenous echoes that were hypoechoic relative to the surrounding tissues, whereas the renal medulla was anechoic to slightly hypoechoic. After treatment, the renal cortex was hyperechoic relative to the surrounding tissue. Increased renal cortex echogenicity was associated with significant nephrotoxicosis and was superior to serum creatinine elevation in nephrotoxicosis detection. Urine GGT was superior to other clinicopathological data utilized in the diagnosis of nephrotoxicosis. Based on the above results, increased renal cortex echogenicity seemed to be of use in detecting of acute renal failure.

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A CASE PRESENTATION OF VERRUCOUS CARCINOMA ORIGINATED FROM VERRRUCOUS LEKOPLAKIA (우췌성 백반증에서 기원한 우췌성 암종의 치험례)

  • Choi, Moon-Gi
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.28 no.4
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    • pp.339-347
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    • 2006
  • Oral leukoplakia is the most common premalignant lesion and malignant transformation has been reported from verrucal lekoplakia. Homogenous, benign leukoplakia develops into a line of squamous cell carcinoma such as verrrucous carcinoma, papillary squamous cell carcinoma and invasive squamous cell carcinoma. Early diagnosis and intervention of premalignant leukoplakia is up-most important to prevent transformation into a oral squamous cell carcinoma. Any change in surface, size and color warrants repeated biopsy. If verrucous carcinoma is evidently derived from the previous leukoplakia, wide surgical excision and periodic follow up is needed. Surgically removed lesion of leukoplakia has the tendency to recur. Follow-up is very important to patient and clinician. Although many therapies have been reported to oral leukoplakia and verrucal carcinoma, accepted treatment principle is not exist so far. But surgical removal is recommended as the treatment of choice.

Study on Bearing Performance Involving the Mixture of Water within Engine Oil in a Turbocharger Journal Bearing (터보챠저 저어널 베어링에서 물과 윤활유가 혼합될 때 베어링 성능에 관한 연구)

  • Chun, Sang-Myung
    • Tribology and Lubricants
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    • v.27 no.4
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    • pp.183-192
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    • 2011
  • In this study, using the governing equations for thermohydrodyamic lubrication involving the homogeneous mixture of incompressible fluid derived by based on the principle of continuum mechanics, it is discussed the effects of water dispersed within engine oil on the performance of high speed journal bearing of a turbocharger. The governing equations are the general equations being able to be applied on the mixture of Newtonian fluid and non-Newtonian fluid. Here, the fluid viscosity index, n of power-law non-Newtonian fluid is supposed to be 1 for the application of the journal bearing on a turbocharger lubricated with the mixture of two Newtonian fluids, water dispersed within engine oil. The results related with the bearing performance are showed that the friction force and bearing load capacity decrease as increasing the volume percent of water.