• 제목/요약/키워드: Horizontal and Vertical Lines

검색결과 172건 처리시간 0.05초

가로흐름에 방류(放流)되는 평면부력(平面浮力)? (Buoyant Slot Jets in Flowing Environment)

  • 윤태훈;한운우
    • 대한토목학회논문집
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    • 제8권3호
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    • pp.53-60
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    • 1988
  • 가로흐름으로 방류(放流)되는 연직상향평면부력(鉛直上向平面浮力)?의 거동(擧動)이 실험과 기본방정식(基本方程式)의 적분기법(積分技法)에 의하여 해석된다. 적분기법(積分技法)을 상사법칙(相似法則)과 특성(特性)길이를 도입한 연직상향 및 수평방향흐름영역에 대한 점근해(漸近解)이며, 실험은 상이한 속도비와 방류밀도 Froude 수를 변화시키면서 수행되었다. 실험결과(實驗結果)와 해석적해(解析的解)는 잘 일치하여, ?중심선(中心線)의 경로(經路)와 온도(溫度)는 멱법칙(冪法則)으로 표현될 수 있는 것으로 나타났다.

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직사각형 밀폐공간내 자연대류 열전달의 수치해석

  • 민만기
    • 대한설비공학회지:설비저널
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    • 제10권3호
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    • pp.185-219
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    • 1981
  • To analyze two dimensional incompressible laminar natural convection in a rectangular enclosure heated from below and cooled by a horizontal ceiling and two vertical walls, he primitive Navier-Stokes equations and the energy equation were solved numerically in time dependent form by a marker and cell method. A successive over-relaxation method for the elliptic portion of the problem and an explicit method for the parabolic portion were applied for the range of Grashoff number of $5{\times}10^3\;to\;5{\times}10^4$ to get the transient and steady state dimensionless temperature and velocity profiles. For the range of aspect ratio $L/H{\leqq}2.4$ in which only a pair of convection rolls exists mean Nusselt number calculated are as follows : $$N_{NU}0.89\;N_{Gr}^{0.2}(H/L)^{0.45}$$ By path lines drawn by marker particle trajectories roll number of cellular motion were observed for various aspect ratio of the enclosure.

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블록 보간법을 이용한 산업용 로봇의 3차원 위치 보정기법 (A 3-D Position Compensation Method of Industrial Robot Using Block Interpolation)

  • 류항기;우경행;최원호;이재국
    • 제어로봇시스템학회논문지
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    • 제13권3호
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    • pp.235-241
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    • 2007
  • This paper proposes a self-calibration method of robots those are used in industrial assembly lines. The proposed method is a position compensation using laser sensor and vision camera. Because the laser sensor is cross type laser sensor which can scan a horizontal and vertical line, it is efficient way to detect a feature of vehicle and winding shape of vehicle's body. For position compensation of 3-Dimensional axis, we applied block interpolation method. For selecting feature point, pattern matching method is used and 3-D position is selected by Euclidean distance mapping between 462 feature values and evaluated feature point. In order to evaluate the proposed algorithm, experiments are performed in real industrial vehicle assembly line. In results, robot's working point can be displayed 3-D points. These points are used to diagnosis error of position and reselecting working point.

Wind velocity field during thunderstorms

  • Ponte, Jacinto Jr.;Riera, Jorge D.
    • Wind and Structures
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    • 제10권3호
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    • pp.287-300
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    • 2007
  • Wind action is a factor of fundamental importance in the structural design of light or slender constructions. Codes for structural design usually assume that the incident mean wind velocity is parallel to the ground, which constitutes a valid simplification for frequent winds caused by meteorological phenomena such as Extratropical Storms (EPS) or Tropical Storms. Wind effects due to other phenomena, such as thunderstorms, and its combination with EPS winds in so-called squall lines, are simply neglected. In this paper a model that describes the three-dimensional wind velocity field originated from a downburst in a thunderstorm (TS) is proposed. The model is based on a semi empirical representation of an axially-symmetrical flow line pattern that describes a stationary field, modulated by a function that accounts for the evolution of the wind velocity with time. The model allows the generation of a spatially and temporally variable velocity field, which also includes a fluctuating component of the velocity. All parameters employed in the model are related to meteorological variables, which are susceptible of statistical assessment. A background wind is also considered, in order to account for the translational velocity of the thunderstorm, normally due to local wind conditions. When the translation of the TS is caused by an EPS, a squall line is produced, causing the highest wind velocities associated with TS events. The resulting vertical velocity profiles were also studied and compared with existing models, such as the profiles proposed by Vicroy, et al. (1992) and Wood and Kwok (1998). The present model predicts horizontal velocity profiles that depend on the distance to the storm center, effect not considered by previous models, although the various proposals are globally compatible. The model can be applied in any region of interest, once the relevant meteorological variables are known, to simulate the excitation due to TS winds in the design of transmission lines, long-span crossings, cable-stayed bridges, towers or similar structures.

정밀가공을 위한 CAD/CAM/CAT 일괄처리시스템 (CAD/CAM/CAT Turmaround System for Precision Machining)

  • 안중용;김승철;정성종
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1993년도 추계학술대회 논문집
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    • pp.417-422
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    • 1993
  • In order to minimize turnaround of machining in FMS lines, CAD/CAM/CAT integrated system called MascCAM was developed. Developing enhanced CAM and inspection modules in the MascCAM environment, 2D came, 2 $^{1}$2/ D prismatic parts and 3D free-formed surfaces were able to be automatically designed, manufactured and inspected on the machine tools by using AutoCAM and Z-map. Introducing Z-map technique, the MascCAM was able to be interfaceed with and CAD system. Developed QPPGT module generates a quick and fool-proof inspection work to users. A vertical and a horizontal machining center equipped with FANUC OMC were used for experiments. Performance of the system was confirmed by a large amount of experiments.

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부산지역 아파트의 실내디자인 특성에 관한 연구 - 모델하우스의 거실공간을 중심으로 - (A Study on the Characteristics of the Interior Design of the Apartments in Busan - Focused on the living rooms of apartment units in modelhouse -)

  • 윤지영
    • 한국실내디자인학회논문집
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    • 제32호
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    • pp.47-54
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    • 2002
  • This study attempts to analyze the characteristics of interior design of the apartments in Busan that people will reside since 2001 and to find out the effects of minimalism in the interior space. The companies which are in construction of the apartments of more than 50 Pyung were selected, and the design of the living rooms of their model houses were analyzed in terms of the floor plans, architectural elements, furniture and lightings. The results reveals that the living rooms of the newly-distributed apartments in Busan show similar design characteristics without distinctive differences among the companies. The new trends provide a flexible wall which makes it possible to manipulate the number of rooms according to the family preference, art-wall design in one-side of the walls and a coffered ceiling design, which can be interpreted to be closely related to the concept of minimalism with expression of simple horizontal and vertical lines, exclusive use of decorative forms, colors and materials, and use of natural materials

전기, 전자탐사에 의한 경주남부 (입실지역)의 울산 단층 심부구조 (Deep structure of Ulsan fault by electric and EM surveys in ipsil area, South of Kyeongju)

  • 손호응
    • 자원환경지질
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    • 제32권2호
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    • pp.161-167
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    • 1999
  • Electric and electromagnetic surveys were conducted to investigate the deep structure of the Ulsan fault in Ipsil area, south of Kyeongju. On this study, especially high-frequency magnetotelluric method of electromagnetic survey in the frequency range of 10~100,000 Hz was mainly employed to study the deep subsurface configuration. High-frequency MT survey was performed at 70 points of spacing 30~50 m, making 3.8 km survey line. As a survey result, a 2-km-depth 2-D cross-section was achieved. It shows vertical and horizontal subsurface variations of resistivity values. Near-surface layer having low resistivity value becomes thicker eastward up to 800m. There is a steep low resistivity zone in the west side of survey line, and there exists two low resistivity zones dipping west in the east side of survey line. Two low resistivity zones are interpreted to be related to major movement pattern of the Ulsan fault. This suggests that major fault lines are developed on both peripheral sides of the broad fault zone.

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다공성 물질의 환형수직원통내에서의 자연대류 열전달 수치해석 (Numerical Study on Convective Heat Transfer within a Vertical Annular Porous Material)

  • 차기업;김종보
    • 설비공학논문집
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    • 제1권2호
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    • pp.128-137
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    • 1989
  • Numerical solutions for two-dimensional, steady, free convection are presented for a cylinder filled with saturated porous media. An annulus is bounded by inner wall with constant heat flux and two adiabatic horizontal walls with outer wall isothermally cooled. Governing equations are numerically solved for the range of Aspect Ratio 1 to 20, Radius Ratio, 1 to 20, and Rayleigh number, 50 to $10^4$ by Finite Difference method utilizing upwind scheme. Results are presented in terms of stream lines and isotherms, temperature distributions and local Nusselt numbers at the heated wall. Average Nusselt numbers are also presented for the comparisons.

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브래지어 디자인에 대한 시각적 감성연구(제 1보) (A study on the visual sensibility of brassiere design(Part I))

  • 하수진;이경희
    • 한국의류학회지
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    • 제23권5호
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    • pp.635-644
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    • 1999
  • The purpose of this study is to investigate the visual sensibilities of brassiere design. Brassieres were divided into three types according to connection of a cup and a strap. In each type Lace was used where the part of the cup divided by lines which were constructed such as a mold horizontal a vertical a mixed and an oblique design. As a result 39 brassieres were obtained. The experiment has been done for the 39 brassieres with 17 semantic differential bi-polar scales. The subjects were 60 female students majoring in clothing and textiles, The data was analyzed using the statistical SPSS package. The major findings of this research were as follows. 1. As a results of the factor analysis, 3 factors(Attractiveness Appearance. Cuteness) were found to be constructing factors for brassiere image. 2. There were significant differences in the visual evaluation of brassiere design especially in the change of lace. 3. As a result of the regression analysis the images affecting preferences were pretty fascinating natural appropriate sexy and clean.

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역 T형 노치를 가진 4세대 이동통신용 평면형 폴디드 모노폴 안테나 (A Planar Folded Monopole Antenna with Inverted T-Shape Notch in Ground Plane for 4G Mobile Communication)

  • 신호섭;최인태
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2013년도 추계학술대회
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    • pp.893-895
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    • 2013
  • 본 논문에서는 접지면에 역 T형 노치를 넣은 평면형 폴디드 모노폴 안테나를 제안하였다. 제안된 안테나에서는 대역폭을 늘리기 위하여 내부 패치와 외부 패치의 폭들을 점차 넓히는 방향으로 변화를 주었고, 그라운드에 가로와 세로 slit의 길이가 비슷하고 폭은 약 2배 정도 차이가 있는 노치를 넣어 설계 및 모의실험을 하였다.

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