• 제목/요약/키워드: Geometrical Structure

검색결과 656건 처리시간 0.032초

보온용 부직포의 구조적 특성이 열전달에 미치는 영향: 단층구조와 이층구조 부직포의 비교 (The Effect of Geometrical Structure on the Heat Transfer of Insulating Nonwovens: A Comparison of Single and Double Layered Nonwovens)

  • 김희숙
    • 한국생활과학회지
    • /
    • 제7권2호
    • /
    • pp.113-119
    • /
    • 1998
  • The purpose of this study was to investigate the effect of geometrical structure on the heat transfer of insulating nonwovens. Commercially available single and double layered polyester nonwovens have used. Thermal conductivity, k and thermal conductance, h were measured by using a constant temperature sandwich type device at dry and wet state. The results obtained were as follows: 1. Double layered nonwovens showed slightly lower thermal conductance and higher warmability than single layered nonwovens. 2. As moisture regain increased, double layered nonwovens showed higher increasing rate of thermal conductivity than single layered nonwovens.

  • PDF

Using nanotechnology for improving the mechanical behavior of spherical impactor in sport problem via complex networks

  • Bo Jin Cheng;Peng Cheng;Lijun Wang
    • Steel and Composite Structures
    • /
    • 제49권1호
    • /
    • pp.31-45
    • /
    • 2023
  • The network theory studies interconnection between discrete objects to find about the behavior of a collection of objects. Also, nanomaterials are a collection of discrete atoms interconnected together to perform a specific task of mechanical or/and electrical type. Therefore, it is reasonable to use the network theory in the study of behavior of super-molecule in sport nano-scale. In the current study, we aim to examine vibrational behavior of spherical nanostructured composite with different geometrical and materials properties. In this regard, a specific shear deformation displacement theory, classical elasticity theory and analytical solution to find the natural frequency of the spherical nano-composite sport structure equipment. The analytical results are validated by comparison to finite element (FE). Further, a detail comprehensive results of frequency variations are presented in terms of different parameters. It is revealed that the current methodology provides accurate results in comparison to FE results. On the other hand, different geometrical and weight fraction have influential role in determining frequency of the structure.

한글 문자의 인식을 위한 대수적 구조 (Algebraic Structure for the Recognition of Korean Characters)

  • 이주근;주훈
    • 대한전자공학회논문지
    • /
    • 제12권2호
    • /
    • pp.11-17
    • /
    • 1975
  • 이 논문은 한글문자의 자동인식을 위한 기초적인 연구로서 기본문자의 구조에 대해서 검토하였다. 기본문자를 구조, 선분구조 및 물자 graph의 node와의 연결곤계 들 구조를 세가지 측면에서 집합 및 군론에 의한 대수적인 분석을 하고 또 그들의 각 구조의 복잡성에 대한 계릉을 고찰하였다. 나아가서 10개의 모음은 한 요소의 Affine 변환에 의한 연속회전으로 이루어지는 회전변환군 속에서 다수의 동치관계가 존재한다는 것을 기술하므로써, 한글문자의 인식에 있어서는 topological 골격외에 기하적 성질이 특히 중요하다는 것을 아울러 지적 하였다. The paper examined the character structure as a basic study for the recognition of Korean characters. In view of concave structure, line structure and node relationship of character graph, the algebraic structure of the basic Korean characters is are analized. Also, the degree of complexities in their character structure is discussed and classififed. Futhermore, by describing the fact that some equivalence relations are existed between the 10 vowels of rotational transformation group by Affine transformation of one element into another, it could be pointed out that the geometrical properting in addition to the topological properties are very important for the recognition of Korean characters.

  • PDF

Precise measurements of distance using large scale structure formation

  • 송용선;서희종
    • 천문학회보
    • /
    • 제36권2호
    • /
    • pp.51.1-51.1
    • /
    • 2011
  • We introduce new methods to measure distance in precision using large scale structure formation. The accuracy to determine geometrical factors is enhanced in comparison to the previous method known as BAO. We determine both D_A and H simultaneously as well as structure of growth of density fluctuations and peculiar velocities. Our method is independent of any given prior on large scale structure formation such as the shape of spectra.

  • PDF

크리에이티브 패션 디자인의 전개 방법에 관한 연구 (A Study on the Expansion Methodology of Creative Fashion Design)

  • 공미선;채금석
    • 복식
    • /
    • 제55권2호
    • /
    • pp.45-57
    • /
    • 2005
  • The creative fashion design is the technique which ran be obtained through the structural analysis of the relationship between principle, element-combination and idea-expression. In the research, as the results of theoretical survey of design structure and idea-expression, the structural and subjective designs are classified and defined: a. the structural design is analyzed with the existing examples based on the combinational Idea-expression of the O.C.L method, and b. the subjective design is also analyzed connecting the real examples to Cordon method, Synetic method, Association method, and expansive idea-expression-method obtained by the Experiences of Geometrical Combinations. The research can be summarized as follows: 1. The creative fashion design which emphasizes the geometrical structure utilizes the modification method whirh combines the shapes and constructs extraordinary structural beauty coming from the complex structural principle, that is, emphasis and balance. 2. The creative fashion design which emphasizes specific subjects utilizes the modification method which mimics representative and plastic resemblances and constructs symbolic structural beauty coming from the simple structural principle, that is, material elements.

Enhancement of thermal buckling strength of laminated sandwich composite panel structure embedded with shape memory alloy fibre

  • Katariya, Pankaj V.;Panda, Subrata K.;Hirwani, Chetan K.;Mehar, Kulmani;Thakare, Omprakash
    • Smart Structures and Systems
    • /
    • 제20권5호
    • /
    • pp.595-605
    • /
    • 2017
  • The present article reported the thermal buckling strength of the sandwich shell panel structure and subsequent improvement of the same by embedding shape memory alloy (SMA) fibre via a general higher-order mathematical model in conjunction with finite element method. The geometrical distortion of the panel structure due to the temperature is included using Green-Lagrange strain-displacement relations. In addition, the material nonlinearity of SMA fibre due to the elevated thermal environment also incorporated in the current analysis through the marching technique. The final form of the equilibrium equation is obtained by minimising the total potential energy functional and solved computationally with the help of an original MATLAB code. The convergence and the accuracy of the developed model are demonstrated by solving similar kind of published numerical examples including the necessary input parameter. After the necessary establishment of the newly developed numerical solution, the model is extended further to examine the effect of the different structural parameters (side-to-thickness ratios, curvature ratios, core-to-face thickness ratios, volume fractions of SMA fibre and end conditions) on the buckling strength of the SMA embedded sandwich composite shell panel including the different geometrical configurations.