• Title/Summary/Keyword: dimensional properties

Search Result 2,647, Processing Time 0.033 seconds

Fabrication of One-Dimensional Graphene Metal Edge Contact without Graphene Exfoliation

  • Choe, Jeongun;Han, Jaehyun;Yeo, Jong-Souk
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2016.02a
    • /
    • pp.371.2-371.2
    • /
    • 2016
  • Graphene electronics is one of the promising technologies for the next generation electronic devices due to the outstanding properties such as conductivity, high carrier mobility, mechanical, and optical properties along with extended applications using 2 dimensional heterostructures. However, large contact resistance between metal and graphene is one of the major obstacles for commercial application of graphene electronics. In order to achieve low contact resistance, numerous researches have been conducted such as gentle plasma treatment, ultraviolet ozone (UVO) treatment, annealing treatment, and one-dimensional graphene edge contact. In this report, we suggest a fabrication method of one-dimensional graphene metal edge contact without using graphene exfoliation. Graphene is grown on Cu foil by low pressure chemical vapor deposition. Then, the graphene is transferred on $SiO_2/Si$ wafer. The patterning of graphene channel and metal electrode is done by photolithography. $O_2$ plasma is applied to etch out the exposed graphene and then Ti/Au is deposited. As a result, the one-dimensional edge contact geometry is built between metal and graphene. The contact resistance of the fabricated one-dimensional metal-graphene edge contact is compared with the contact resistance of vertically stacked conventional metal-graphene contact.

  • PDF

Relationship between Equilibrium Moisture Contents and Dimensional Stability of Handsheet Depending on Fibers Hornification (섬유의 각질화에 따른 수초지의 평형함수율과 치수안정성의 관계)

  • Park, Chang-Soon;Lee, Jin-Ho;Kil, Jung-Ha;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.43 no.3
    • /
    • pp.11-20
    • /
    • 2011
  • The conditions to which pulp fibers are exposed during paper production, converting, storage, use, and recycling can induce various changes in fiber morphology, surface characteristics, and suitability for paper production by recycled fibers. Most of those changes can be described by hornification. Paper has highly hygroscopic properties which affect dimensional change by relative humidity variation of surrounding condition. The purpose of this study was to investigate the dimensional stability, moisture contents and dip elongation of handsheets at different relative humidity conditions of recycled kraft pulp and BCTMP. By using recycled fibers, dimensional stability was increased because hygroscopic properties of fibers decreased with repeated recycling treatment. Dip elongation of recycled pulp was higher than that of virgin pulp because of its weak fiber-to-fiber bonding. By recycling pulp, the relative bonded area was decreased because fiber could not swell more than virgin pulp. Dimensional stability largely depended on the equilibrium moisture contents of paper, the fiber-to-fiber bonding strength, and the relative bonded area.

3D Modeling Method for Cultural Properties Web GIS Database Construction (Web GIS 도형 자료 구축을 위한 문화재 3차원 모델링 기법)

  • Jung, Sung-Hyuk;Lee, Jae-Kee
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.12 no.2 s.29
    • /
    • pp.37-42
    • /
    • 2004
  • The purpose of this study is not only preserving and restoring our nation's precious cultural inheritances transmitted for half millennia but informing the world of them. This study also aims recognizing the necessity of transmitting them to prosperity, constructing three-dimensional database by using a photogrammetry and VRML method and utilizing basic data of treasure exhibition with the progress of exhibition technique development on cyber space. Therefore, in this study, I suggest three dimensional modeling method that acquire three dimensional database about cultural properties through photogrammetry method which can acquire three-dimensional coordinates with easy and can express various color and stuff-feeling by using VRML.

  • PDF

Mechanical Properties of Three-dimensional Glass Fabric-reinforced Vinyl Ester Matrix Composites (삼차원 유리직물 강화 비닐에스테르 복합재의 기계적 특성)

  • Park, Won-Bae;Park, Soo-Jin;Lee, Jae-Rock
    • Applied Chemistry for Engineering
    • /
    • v.9 no.5
    • /
    • pp.715-718
    • /
    • 1998
  • In this work, bisphenol type vinyl ester was impregnated into the three-dimensional glass fabrics fabricated from different thickness changes. Their mechanical properties of the specimens have been investigated by three-point bending and flatwise compression tests. Also, interlaminar shear strength (ILSS) has been determined through short-beam test for the evaluation of interfacial adhesion at interfaces between fibers and matrix of the composites. The effect of thickness changes in three-dimensional glass fabric-reinforced composites have been described in this work.

  • PDF

Effect of Degradation of Rock Mass Properties Caused by Water Pressure on the Stability of Mine Gallery (수압에 의한 암반의 물성 저하가 갱도의 안정성에 미치는 영향)

  • Yoon, Yong-Kyun;Baek, Young-Jun;Jo, Young-Do
    • Tunnel and Underground Space
    • /
    • v.21 no.2
    • /
    • pp.138-144
    • /
    • 2011
  • Mine closure does often accompany the flooding of mine galleries due to ceasing a pumping operation. When a mine gallery is flooded, rocks around the gallery are fully saturated and the gallery is subject to a water pressure. The uniaxial unconfined compressive strength of a rock depends on its water content and decreases as the water content increases. A water pressure may originate the crack growth of a rock or the discontinuity growth of rock mass. Although the water in a gallery will give some support pressure inside the gallery, the degradation of rock mass properties caused by a water pressure will reduce the stability of the gallery. In this study, 2-dimensional discontinuous and 3-dimensional continuous numerical analyses have been conducted to evaluate an effect that a reduction of rock mass properties around the gallery induced by a water pressure has on the stability of mine gallery. The numerical analyses show that a reduction of rock mass properties caused by a water pressure increases displacements of rock mass around mine gallery. 2-dimensional model is found to give larger values of displacement than 3-dimensional model.

A Study on Three-dimensional Effects and Deformation of Textile Fabrics: Dynamic Deformations of Silk Fabrics

  • Kim, Minjin;Kim, Jongjun
    • Journal of Fashion Business
    • /
    • v.17 no.6
    • /
    • pp.28-43
    • /
    • 2013
  • Recent trends toward the collaborations among various sectors of academia and research areas have brought interests and significances in new activities especially in the fashion and textile areas. One of the collaboration examples is the recent research projects on 3D virtual clothing systems based on the 3D CAD software. The 3D virtual clothing systems provide simulated apparels with high degrees of fidelity in terms of color, texture, and structural details. However, since real fabrics exhibit strong nonlinearity, anisotropy, viscoelasticity, and hysteresis, the 3D virtual clothing systems need fine tuning parameters for the simulation process. In this study, characteristics of silk fabrics, which are woven by using degummed silk and raw silk yarns, are being analyzed and compared. Anisotropic properties may be measured as warp and filling direction properties separately in woven fabrics, such as warp tensile stress or filling bending rigidity. Hysteretic properties may be measured as bending hysteresis or shear hysteresis by using KES measurements. These data provide deformation-force relationships of the fabric specimen. Three-dimensional effects obtained when using these characteristic fabrics are also analyzed. The methods to control the three-dimensional appearance of the sewn fabric specimens when utilizing a programmable microprocessor-based motor device, as prepared in this study, are presented. Based on the physical and mechanical properties measured when using the KES equipment, the property parameters are being into a 3-dimensional virtual digital clothing system, in order to generate a virtual clothing product based on the measured silk fabric properties.

Dislocations as native nanostructures - electronic properties

  • Reiche, Manfred;Kittler, Martin;Uebensee, Hartmut;Pippel, Eckhard;Hopfe, Sigrid
    • Advances in nano research
    • /
    • v.2 no.1
    • /
    • pp.1-14
    • /
    • 2014
  • Dislocations are basic crystal defects and represent one-dimensional native nanostructures embedded in a perfect crystalline matrix. Their structure is predefined by crystal symmetry. Two-dimensional, self-organized arrays of such nanostructures are realized reproducibly using specific preparation conditions (semiconductor wafer direct bonding). This technique allows separating dislocations up to a few hundred nanometers which enables electrical measurements of only a few, or, in the ideal case, of an individual dislocation. Electrical properties of dislocations in silicon were measured using MOSFETs as test structures. It is shown that an increase of the drain current results for nMOSFETs which is caused by a high concentration of electrons on dislocations in p-type material. The number of electrons on a dislocation is estimated from device simulations. This leads to the conclusion that metallic-like conduction exists along dislocations in this material caused by a one-dimensional carrier confinement. On the other hand, measurements of pMOSFETs prepared in n-type silicon proved the dominant transport of holes along dislocations. The experimentally measured increase of the drain current, however, is here not only caused by an higher hole concentration on these defects but also by an increasing hole mobility along dislocations. All the data proved for the first time the ambipolar behavior of dislocations in silicon. Dislocations in p-type Si form efficient one-dimensional channels for electrons, while dislocations in n-type material cause one-dimensional channels for holes.

EXTENSION OF MULTI-DIMENSIONAL LIMITING PROCESS ONTO THREE-DIMENSIONAL UNSTRUCTURED GRIDS (다차원 공간 제한 기법의 3차원 비정렬 격자계로 확장)

  • Park, J.S.;Kim, C.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2010.05a
    • /
    • pp.404-411
    • /
    • 2010
  • The present paper deals with the continuous work of extending multi-dimensional limiting process (MLP), which has been quite successfully proposed on two- and three-dimensional structured grids, onto the unstructured grids. The basic idea of the present limiting strategy is to control the distribution of both cell-centered and cell-vertex physical properties to mimic a multi-dimensional nature of flow physics, which can be formulated as so called the MLP condition. The MLP condition can guarantee a high-order spatial accuracy without yielding spurious oscillations. Recently, MLP slope limiter was proposed based on the MUSCL-type reconstruction in two-dimensional case and it can be readily extended to three-dimensional case. Through various numerical analyses and extensive computations, it is observed that the proposed limiters are quite effective in controlling numerical oscillations and very accurate in capturing both discontinuous and continuous multi-dimensional flow features on 3-D tetrahedral grids.

  • PDF

REFLECTIONS OF COMPLETELY REGULAR AND ZERO-DIMENSIONAL QUASI-ORDERED SPACES

  • Shin, Seon-Ho
    • The Pure and Applied Mathematics
    • /
    • v.10 no.1
    • /
    • pp.25-35
    • /
    • 2003
  • We study equivalent definitions and some categorical properties of completely regular quasi-ordered spaces and zero-dimensional quasi-ordered spaces. Using the o-completely regular (resp. o-zero-dimensional) filters on a completely regular (resp. zero-dimensional) quasi-ordered space, we show that the category COMPOS (resp. ZCOMPOS) of compact (resp. compact zero-dimensional) partially ordered spaces is reflective in the category CRQOS (resp. ZQOS) of completely regular (resp. zero-dimensional) quasi-ordered spaces and continuous isotones.

  • PDF

Examination of Two-Dimensional Magnetic Properties in a 5-Leg-Different- Volume- V-Connection- Transformer Core

  • Urata Shinya;Shimoji Hiroyasu;Todaka Takashi;Enokizono Masato
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
    • /
    • v.5B no.3
    • /
    • pp.243-247
    • /
    • 2005
  • The Different-volume- V-connection transformer is known as an electric power source that can supply 3-phase electric power and single-phase electric power at the same time. Usually, we use two single-phase transformers that have different volumes. In this paper, we propose the use of a 3-phase 5-leg transformer with the different-volume- V-connection. And, we examine the magnetic properties of the 5-leg core model with the different-volume- V-connection. The magnetic properties of cores with the different-volume- V-connection are compared with those with the delta-connection. In order to express the magnetic anisotropy of the core materials and to calculate the iron loss directly, the two-dimensional vector magnetic property is considered with the E&SS modeling in the simulation.