• Title/Summary/Keyword: basic structure

Search Result 4,468, Processing Time 0.04 seconds

A basic research for knowledge-based management of feature recognition rules (형상인식 규칙의 지식 베이스 운용에 관한 연구)

  • 박재홍;반갑수;이석희
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1991.10a
    • /
    • pp.715-719
    • /
    • 1991
  • In manufacturing process, usually 2-dimensional part drawing is used as a basic data. If a designer wants to recognize 2-dimensional drawing and formulate 3-dimensional shape, a proper feature recognition rule is required as a prerequisite step. These rules are converted Into knowledge base, should be ed separately in the recognition program and can be referenced In similar way of database application. In this paper, basic feature recognition rules are addressed in structure type knowledge base, and the application system is formulated which can be operated separately with existing data driven program.

  • PDF

A Study on the Strength Characteristics of the Pin Jointed CFRP Composites for Cryogenic Supporting Structure (극저온 지지구조물을 위한 CFRP 적층판의 핀 체결부 강도특성 연구)

  • Her, N.I.;Kim, J.H.;Lee, Y.S.;Kim, H.K.;Bak, J.S.;Kwon, M.
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2002.02a
    • /
    • pp.173-176
    • /
    • 2002
  • Fundamental failure mode in a laminated composite pinned joint is proposed to assess damage resulting from stress concentration in the plate. The joint area is a region with stress concentrations thus a complicated stress state exists. The modeling of damage in a laminated composite pinned joint presents many difficulties because of the complexity of the failure process. In this study, the effect on the bearing strength of the pin jointed Carbon Fiber Reinforced Plastics (CFRP) composites for magnet support structure of KSTAR tokamak with various parameters such as edge distance to diameter, width to diameter, and the temperature of $23^{\circ}C$, $-76^{\circ}C$, and $-196^{\circ}C$ was examined by comparing the experimental results with finite element analysis.

  • PDF

Studies on The Elution Behavior of Ni(II)-${\alpha}$-isonitroso-${\beta}$-diketone Imine Chelates in Reversed-Phase Liquid Chromatography

  • Lee, Won;Kim, In-Whan;Kim, Mi-Kyoung;Kim, Yong-Jun;Jung, Hae-Rim;No, Kyoung-Tai;Kim, Su-Yeon
    • Analytical Science and Technology
    • /
    • v.8 no.4
    • /
    • pp.519-527
    • /
    • 1995
  • The retention mechanism of Ni(II)-${\alpha}$-isonitroso-${\beta}$-diketone imine chelates in reversed-phase HPLC has been studied by examining the effect of temperature, mobile phase composition in acetonitrile-water mixture, and molecular structure on retention. The empirical retention equation was investigated to evaluate the properties of S (hydrophilic index). The value of the S index of the Ni(II) chelates decrease with the increasing column temperature and a linear relationship between S and log $k{_w}^{\prime}$ has been found. The results showed that the S index is influenced by the interaction between Ni(II) chelates and mobile phase. Molecular properties, van der Waals molar volume, polarizability and dipole moment, of the Ni(II) chelates were calculated by Cerius 2 program and the calculations were performed at Universal Force Field (UFF) model. The S value and log $k{_w}^{\prime}$ increase with decreasing the dipole moment of Ni(II) chelates.

  • PDF

A Mechanistic Study on Addition Reactions of Alicyclic Amines to 3-Butyn-2-one

  • 음익환;이정숙;육성민
    • Bulletin of the Korean Chemical Society
    • /
    • v.19 no.7
    • /
    • pp.776-779
    • /
    • 1998
  • Second-order rate constants have been measured spectrophotometrically for the addition reaction of a series of alicyclic amines to 3-butyn-2-one to yield their respective enamines at 25.0 'C. The reactivity of the amines increases with increasing the basicity of the amines. However, the Bronsted-type plot obtained exhibits a downward curvature as the basicity of the amines increases, i.e. βnuc decreases from 0.3 for low basic amines (pKa < 9) and to 0.1 for highly basic amines (pKa > 9). Such a curvature in the Bronsted-type plot is clearly indicative of a change in the reaction mechanism or transition state structure. From the corresponding reactions run in D2O, the magnitude of kinetic isotope effect (KIE) has been calculated to be about 0.8 for highly basic amines and 1.21 for weakly basic amines. The difference in the magnitude of KIE also supports a change in the reaction mechanism or transition state structure upon changing the basicity of the amines. Furthermore, the small KIE clearly suggests that H+ transfer is not involved in the rate-determining step, i.e. the addition reaction is considered to proceed via a stepwise mechanism in which the attack of the amines to the acetylene is the rate-determining step. The curvature in the Bronsted-type plot has been attributed to a change in the degree of bond formation between the amine and the acetylene.

PACVD of Plasma Polymerized Organic Thin Films and Comparison of their Electrochemical Properties

  • I.S. Bae;S.H. Cho;Kim, M.C.;Y.H. Roh;J.H. Boo
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2003.05a
    • /
    • pp.53-53
    • /
    • 2003
  • Plasma polymerized organic thin films were deposited on Si(100) glass and metal substrates using thiophene and ethylcyclohexane precursors by PECVD method. In order to compare electrochemical properties of the as-grown thin films, the effects of the RF plasma power in the range of 30~100 W. AFM showed that the polymer films with smooth surface and sharp interface could be grown under various deposition conditions. Impedance analyzer was utilized for the determination of I-V curve for leakage current density and C-V for dielectric constants, respectively. To obtain C-V curve, we used a MIM structure of metal(Al)-insulator(plasma polymerized thin film)-metal(Pt) structure. Al as the electrode was evaporated on the thiophene films that grew on Pt coated silicon substrates, and the dielectric constants of the as-grown films were then calculated from C- V data measured at 1MHz. From the electrical property measurements such as I-V and C-V characteristics, the minimum dielectric constant and the best leakage current of thiophene thin films were obtained to be about 3.22 and $1{\;}{\times}10^{-11}{\;}A/cm^2$. However, in case of ethylcyclohexane thin films, the minimum dielectric constant and the best leakage current were obtained to be about 3.11 and $5{\;}{\times}10^{-12}{\;}A/cm^2$.

  • PDF

GENERALIZED BIPRODUCT HOPF ALGEBRAS

  • Park, Junseok
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.21 no.3
    • /
    • pp.301-320
    • /
    • 2008
  • The smash product algebra has been generalized to general smash product algebra in [3] and we can generalize the smash coproduct coalgebra to obtain the general smash coproduct coalgebra. It is natural to replace the smash product and smash coproduct by the generalized smash product and generalized smash coproduct and consider the condition under which the generalized smash product algebra structure and the generalized smash coproduct coalgebra structure will inherit a bialgebra structure or a Hopf algebra structure. We derive necessary sufficient conditions for the problem. This generalizes the corresponding results in [7] and [4].

  • PDF

Design of Coupled Resonators Bandpass Filter with Defected Ground Structure

  • Kim, Gi-Rae
    • Journal of information and communication convergence engineering
    • /
    • v.9 no.2
    • /
    • pp.150-154
    • /
    • 2011
  • In this paper a four-pole elliptic function bandpass filter is designed with two ground slots. A research of microstrip bandpass filters (BPF) using defected ground structures (DGS) is presented. DGS technique allows designs of tight couplings without the necessity of using very narrow coupling gaps. The simulator Sonnet is used to design the resonator and to calculate the coupling coefficient of the basic coupling structure. Compared to similar microstrip filters without defected ground structure, the simulated performances of these novel structures indicate some technological advantages.

The Determinant Factors of Basic Concept in the Residential Site Planning - Focus on Physical Planning Elements - (주거단지계획 기본구상 결정요인에 관한 연구 - 물리적 계획요소를 중심으로 -)

  • Cho, sung-Hak
    • Journal of the Korean housing association
    • /
    • v.28 no.2
    • /
    • pp.67-74
    • /
    • 2017
  • The purpose of this study is to present basic data of basic concept that planners should consider in planning process. For this purpose, we have proposed the determinant factors of basic concept. In particular, this study focuses on the physical planning elements among the various planning elements that determine the basic concept. The research method is the case study and analysis for the competitions of LH for the past four years. After dividing the residential environment area, the planning elements was derived and the planning direction is arranged for the case district. The determinants factor were determined by the structure of each area. Three area, including the degree of urban context, were found to be the main determinants of the basic idea. The results of the study are as follows. (1) The degree of reflection of urban context, the degree of effort to resolve environmental influences are determinant factors of basic concept. (2) The degree of connection between urban and site area, the degree of overlapping of the boundaries, and street are determinant factors of basic concept. (3) The degree of appropriateness of the residential layout, the degree of rationality of the moving plan, the adequacy of the community space plan are determinant factors of basic concept.

A Study on the Spatial Characteristics from the "The Holy Trinity" Fresco Painted by Masaccio (마사치오의 "삼위일체" 벽화에서 나타난 공간적인 특성에 관한 연구)

  • Kim, Seok-Man
    • Journal of architectural history
    • /
    • v.22 no.6
    • /
    • pp.7-22
    • /
    • 2013
  • The purpose of this paper is to study on the spatial characteristics from the "The Holy Trinity" fresco painted by Masaccio in the early Renaissance paintings. The results of this study are as follows. 1. The elevation composition of the "The Holy Trinity" fresco is divided into the upper and lower structure through horizontal axis on horizontal line around vanishing point. The upper structure is composed of vertical axis formed through the disposition of the "Trinity" elements and horizontal axis on horizontal line. The lower structure is composed of the sarcophagus and skeleton in such inside and the altar supported through circular columns of left and right. 2. The section composition of the "The Holy Trinity" fresco is composed of the ceiling structure of cylindrical-shaped vault on upper part around basic square floor plan that is interior space and upper structure. The exterior space and lower structure is placed with sarcophagus in inner part that altar and step is projected as same height and width in the outside direction. 3. The basic floor composition of the "The Holy Trinity" fresco is planned by square shape around structural columns that is placed at corners as symmetry through transverse, longitudinal and diagonal axis. The whole floor composition planned through the altar and step that is in exterior space at front, the apse of round form at rear part and the structure of the middle story concept at interior. 4. The visual aspect of the "The Holy Trinity" fresco is composed of the stable balance in relation with distance and height because the interior and exterior space as well as the upper structure and lower structure is formed by regular proportion system. The elevation angle of visual range was planned to view in detail generally or partially the architectural composition system and element, characters through proper visual distance, center and position.