• Title/Summary/Keyword: 삼각형 변요소

Search Result 8, Processing Time 0.026 seconds

Development of Mesh Generator for 2D Hydraulic Analysis(III) (2차원 수리 해석을 위한 범용 Mesh Generator의 개발(III))

  • Kim, Do-Hun;Jang, Hyung-Sang;Goh, Tae-Jin;Kim, Hong-Sik
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2007.05a
    • /
    • pp.398-402
    • /
    • 2007
  • 본 연구에서는 삼각 요소망을 구성하는데 사용되는 기존의 Delaunay Triangulation 기법 외에 Advanced Front Technique 알고리즘을 적용하여 하천의 경계가 중요시되는 해석 모델에 적합한 삼각 요소망을 생성하고자 한다. Advanced Front Technique 알고리즘은 외부 경계를 따라 삼각 요소를 형성하기 시작하여 전체 해석 영역으로 요소를 채워가는 방법이다. 이 방법은 위에서 언급한 Delaunay Triangulation 기법의 단점인 해석 영역의 경계에서 요소의 형질이 좋지 못한 문제를 극복할 수 있을 뿐만 아니라, 미리 절점을 생성하지 않으므로 메모리를 절약하는 효과도 얻게 된다. Advanced Front Technique 알고리즘은 외부 경계의 노드(i)와 노드(i+1)을 Front로 하고, 이등변삼각형을 이루기 위해 해석 영역 내부의 적절한 위치에 새로운 절점(C)을 생성한다. 이렇게 Front와 새로운 절점(C)으로 이루어진 이등변 삼각형 요소가 생성된 후에, Front는 다음 Front로 전진하면서 점차 해석 영역의 내부로 삼각형 요소를 채우게 된다. 이와 같은 방법에 의해서 해석영역의 경계에서는 비교적 이등변 삼각형에 가까운 삼각 요소가 생성된다.

  • PDF

Study on the Meaning of 'Side' in Geometry and Methods of its Introduction in Mathematics Textbook (도형영역에서의 '변(邊)'의 의미 및 도입방법에 대한 고찰)

  • Kim, Soomi
    • Journal of Elementary Mathematics Education in Korea
    • /
    • v.18 no.3
    • /
    • pp.441-457
    • /
    • 2014
  • This study starts with the idea that Korean mathematical word 'byon' which means 'side' of polygons or angles is very ambiguous. The purpose of this study is to make the concept and range of 'byon' clear and to suggest the ideas which can help children understand the concept of 'byon'. For this, various dictionary and the past Korean mathematics curriculums are reviewed. As a result, two attributes 'byon' has are identified and some reasons which block children from understanding 'byon' are detected in its introduction method of mathematics text books and inkhorn of the mathematical term. Finally, two different ideas for helping children understand the concept 'byon' are suggested based on the conclusion of this research.

  • PDF

Near electromagnetic field analysis of HTS microstrip patch antenna (고온초전도 마이크로스트립 패치 안테나의 근거리 전자장 해석)

  • 정동철;허원일;김민기;한태희;한병성
    • Electrical & Electronic Materials
    • /
    • v.9 no.8
    • /
    • pp.783-788
    • /
    • 1996
  • In this paper, the high-$T_c$ , superconductor (HTS) microstrip patch antenna which is directly coupled to a microstrip transmission line is designed and the numerical solution which evaluate near electromagnetic field of HTS antenna is presented. This solution uses the interpolation function with the vector edge triangular element. The advantage of this element is the elimination of spurious solutions attributed to the lack of enforcement of the divergence condition. The results of this method have a good agreement with $TM_10$ mode in HTS microstrip patch antenna and show that the computation of resonant length considering the fringing capacitance effect at radiating edge are proper.

  • PDF

Effect of thread design on the marginal bone stresses around dental implant (임플란트 나사산 디자인이 변연골 응력에 미치는 영향)

  • Lee, Sang-Hyun;Jo, Kwang-Heon;Lee, Kyu-Bok
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.49 no.4
    • /
    • pp.316-323
    • /
    • 2011
  • Purpose: The purpose of this study was to investigate the effect of different thread designs on the marginal bone stresses around dental implant. Materials and methods: Standard ITI implant(ITI Dental Implant System; Straumann AG, Waldenburg, Switzerland), 4.1 mm in diameter and 10 mm in length, was selected as control. Test implants of four different thread patterns were created based on control implant, i.e. maintaining all geometrical design of control implant except thread pattern. Four thread designs used in test implants include (1) small V-shape screw (model A), (2) large V-shape screw (model B), (3) buttress screw (model C), and (4) trapezoid screw (model D). Surface area for unit length of implant was 14.4 $mm^2$ (control), 21.7 (small V-shape screw), 20.6 (large V-shape screw), 17.0 (buttress screw) and 28.7 $mm^2$ (trapezoid screw). Finite element models of implant/bone complex were created using an axisymmetric scheme with the use of NISA II/DISPLAY III (Engineering Mechanics Research Corporation, Troy, MI, USA). A load of 100 N applied to the central node on the crown top either in parallel direction or at 30 degree to the implant axis (in order to apply non-axial load to the implant NKTP type 34 element was employed). Quantification and comparison of the peak stress in the marginal bone of each implant model was made using a series of regression analyses based on the stress data calculated at the 5 reference points which were set at 0.2, 0.4, 0.6, 0.8 and 1.0 mm from implant wall on the marginal bone surface. Results: Results showed that although severe stress concentration on the marginal bone cannot be avoided a substantial reduction in the peak stress is achievable using different thread design. The peak marginal bone stresses under vertical loading condition were 7.84, 6.45, 5.96, 6.85, 5.39 MPa for control and model A, B, C and D, respectively. And 29.18, 26.45, 25.12, 27.37, 23.58 MPa when subject to inclined loading. Conclusion: It was concluded that the thread design is an important influential factor to the marginal bone stresses.

A Study on The eigen-properties on Varied Structural 2-Dim. Waveguides by Krylov-Schur Iteration Method (Krylov-Schur 순환법을 이용한 다양한 2차원 구조의 도파관들에 관한 연구)

  • Kim, Yeong Min;Lim, Jong Soo
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.51 no.2
    • /
    • pp.10-14
    • /
    • 2014
  • Krylov-Schur iteration method has been applied to the 2-Dim. waveguides of the varied geometrical structure. The eigen-equations for them have been constructed from FEM based on the tangential edge vectors of triangular elements. The eigen-values and their modes have been determined from the diagonal components of the Schur matrices and its transforming matrices. The eigen-pairs as the results have been revealed visually in the schematic representations.

Fracture Simulation of UHPFRC Girder with the Interface Type Model (경계형 모델을 사용한 초고강도 섬유보강 콘크리트거더의 파괴역학적 해석)

  • Guo, Yi-Hong;Han, Sang-Mook
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.23 no.1
    • /
    • pp.81-94
    • /
    • 2010
  • This paper deals with the fracture simulation of UHPFRC girder with the interface type model. Based on the existing numerical simulation of quasi-brittle fracture in normal strength concrete, constitutive modeling for UHPFRC I-girder has been improved by including a tensile hardening at the failure surface. The finite element formulation is based on a triangular unit, constructed from constant strain triangles, with nodes along its sides and neither at the vertex nor the center of the unit. Fracture is simulated through a hardening/softening fracture constitutive law in tension, a softening fracture constitutive law in shear as well as in compression at the boundary nodes, with the material within the triangular unit remaining linear elastic. LCP is used to formulate the path-dependent hardening-softening behavior in non-holonomic rate form and a mathematical programming algorithm is employed to solve the LCP. The piece-wise linear inelastic yielding-failure/failure surface is modeled with two compressive caps, two Mohr-Coulomb failure surfaces, a tensile yielding surface and a tensile failure surface. The comparison between test results and numerical results indicates this method effectively simulates the deformation and failure of specimen.

The Symbolism of Korean 'Gat' and the Etymology of 'Hat' (영어 'Hat'가 된 한국 '갓' 의 상징성)

  • Hyo Jeong Lee;Youngjoo Na
    • Science of Emotion and Sensibility
    • /
    • v.25 no.4
    • /
    • pp.3-20
    • /
    • 2022
  • The origins of the world-recognized Korean gat can be traced back to Gojoseon, and the jades for the sangtu and gwanja come from Hongshan culture. This study examines the etymology of the hat, the symbolism of the gat and the jade comb, and the history of the development of the accessories for the hat. The research methods of literature review, investigation of relics and murals, and analysis of cases of pronunciation changes were used. Most of the relics excavated from the Hongshan are identical to those excavated from Korea. The Byun-Khan people wore a triangle-shaped conical hat (the byun), which was shaped to fit the protruding sangtu hairstyle, with a foldable brim that, if pulled downward, changed the hat to a gat. The Chu sangtu, a pointed top-knot hairstyle, is uniquely found among Northeast Asian peoples, and it is an ethnic symbol for Koreans. Until the modern period, many Koreans wore their hair in the sangtu style, indicating their descent from the sky. Jade combs shaped like birds and clouds from the Hongshan period emphasized the religious nature and ceremony of hair styling at that period. The word hat is widely used to refer to gat all over the world. The pronunciation of ㄱg, ㅎh. and ㅋq/kh are closely related to each other, and the ancient pronunciation ㄱg gradually evolved to ㅎh or ㅋq/kh. The English 'Hat' and Korean 'Gat' were transformed from the middle-ancient sound 'gasa > gosa > got' of the crown 'gwan, gokkal'. This creative hair style culture that started from the Hongshan culture continued to be fashionable during the Gojoseon Dangun period, and the decoration techniques for hats and accessories were inherited over time and continuously developed. Along with the method of making gat, creative hair-related parts, such as manggeons, donggot pins, gwanja buttons, and fine combs were developed over the course of a thousand years.

Dispersion of Standing Stones at Noseongsan(Mt.Noseong) and Aspect of the Stone Decorated Garden(Soo-suk Jeongwon) at Chongsuk-Sa(Chongsuk Buddhist Temple) in Nonsan City (논산 노성산(魯城山)의 입석(立石) 분포와 총석사(叢石寺) 수석(樹石)의 정원적 면모)

  • Rho, Jae Hyun;Huh, Joon;Jang, Il Young
    • Korean Journal of Heritage: History & Science
    • /
    • v.43 no.1
    • /
    • pp.160-189
    • /
    • 2010
  • This study has been designed to grasp the present situation, shapes and meaning of the standing stones and rock pillars in the whole area of Noseong Mountain Fortress in Nonsan City which have never been academically reported yet. Accordingly, the research was carried out to grasp the spatial identity of Noseong Mt. and Noseong Mountain Fortress and the dispersion of standing stones scattered around inside and outside Noseong Mountain Fortress, while the shapes and structural characteristics of stones were investigated and analyzed focusing on Chongsuk Temple, which was considered to have the highest density of standing stones and greatest values for preservation as a cultural property. In consideration of the reference to the 'Top Sa' (tower temple) at the 'Bul Woo Jo' (Article about Buddhism Houses) of 'Shinjoong Dongguk Yeoji Seungram', theoretical existence of the temple according to surveying investigation, and the excavation records of roof tile pieces with the name of 'Gwan Eum Temple', it is presumed that there had been a Buddhist sanctum inside the fortress and it could be connected to the carved letters, 'Chongsuk Temple'. According the observation survey, the 6th place of standing stones among many other places inside the fortress shows that Chongsuk Temple appears to have the strong characteristics of artificially constructed space in consideration of the size of trees and stones, the composite trend of tree and stone composition, and trace of the adjacent well and strand and the construction of stairway leading to the stone gate. Along with the constellation of the Big Dipper carved on a rock at the same space, the stones, on which the letters of 'Shinseonam', 'Chilseongam' and 'Daejangam' were carved, including 'Chongsuksa', and the carved statue of Buddha, which was assumed to be Avalokitesvara Guan Yin, have offered clue which make it possible to infer that the space was a space for Chilseong and Mountain god(Folk Belief) that had originated from the combination of Buddhism, Taoism and folk religion. According to the actual measurement of standing stones at Chonsuk Temple, it was identified that there were big differences in height among 24 stones in total, ranging from 402~29cm and the averaged distance between each stone appeared to be 23.6cm. And the shape of stones appeared to be standing or flat, and various stones such as mountain-like stones and Buddha-like stones were placed in a special arrangement or assorted arrangement, but the direction of the stones had a consistency pointing to the west. And comparing to the trace of construction of ZEN Landscape Garden well known in the country, the three flat stones except for the standing and shaped stones appeared to have the shape of meditation statue, which is the typical formational factors of a ZEN Landscape Garden, on the basis of formational technique of stones. Among them, the flat stone facing the Buddhist saint statue, was formed by way of symbolization of three-mountain stone, which was assumed to be an offering stone for sacrificial food rather than carrying out ZEN Meditation. In consideration of the formation of standing stones at Chong-suk Temple, which was carried out in the composite stoning method based using the scalene triangle with ratio of 3:5:7 in order to seek the in-depth beauty based on the stone statues of three Buddhas where the three factors such as heaven, earth and humans are embodied in the elevated or flat formation, the stones at Chongsuk Temple and the space seemed to the trace of contracted garden construction that was formed with stones for a temple, so that could be used for ZEN meditation.