• Title/Summary/Keyword: open length

Search Result 1,003, Processing Time 0.031 seconds

Design of a Variable-Length Instruction based on a OpenGL ES 2.0 API (OpenGL ES 2.0 API 기반 가변길이 명령어 설계)

  • Lee, Kwang-Yeob
    • Journal of IKEEE
    • /
    • v.12 no.2
    • /
    • pp.118-123
    • /
    • 2008
  • The Khronos group releases OpenGL ES 2.0 API specification bringing streamlined shader programming to graphics processor of embedded system. For this reason, the mobile devices have need of graphics processor for supporting a OpenGL ES 2.0 API. We need to extend instruction`s length to support OpenGLES 2.0 API, so it needs more memory size. In this paper, we propose a new instruction format that offers availability for use the instructions. This proposed instruction adopt a variable length method and unit instruction architecture. This proposed instruction architecture that support to OpenGLES 2.0 API has consist of 32bit unit instructions up to 4 which can be combined for embellishing each other. Therefore, it can execute flexible instruction combination and reduce waste of instruction fields.

  • PDF

Evaluating the Accuracy of an OpenCV-Based Length Measurement Algorithm: The Impact of Checkerboard Type and Capturing Conditions (체커보드 종류 및 촬영조건에 따른 OpenCV 기반 길이측정 알고리즘 정확도 분석)

  • Kim, Hyeonmin;Kwon, Woobin;Kim, Harim;Kim, Hyungjun;Song, Seung Ho;Cho, Hunhee
    • Journal of the Korea Institute of Building Construction
    • /
    • v.24 no.1
    • /
    • pp.133-144
    • /
    • 2024
  • The OpenCV-based length measurement algorithm is anticipated to be effective for length measurement inspection tasks, providing objective inspection outcomes. Nonetheless, there is a notable gap in research regarding the influence of various checkerboard types and capturing conditions on the algorithm's accuracy in real-world construction settings. Consequently, this study proposes a methodology employing an OpenCV-based length measurement algorithm and checkerboard for digital construction inspection tasks. The findings suggest that using a checkerboard with square sizes of A4 or larger, and 50mm or larger, is optimal for capturing distances and angles within 4m and 90°, respectively, when deploying the algorithm. These insights are anticipated to provide practical guidelines for professionals conducting digital-based length measurement inspections.

An Experimental Study on the Characteristics for Open-Tube and Closed-Tube Thermoacoustic Effects (2)- The 2nd, 3rd Harmonic (개방관과 밀폐관의 열음향 효과에 관한 하모닉 특성 연구(2) - 2차, 3차 하모닉)

  • 송규조;박종호;이성노
    • Progress in Superconductivity and Cryogenics
    • /
    • v.4 no.1
    • /
    • pp.135-139
    • /
    • 2002
  • In this study, the experimental open-tube and close-tube thermoacoustic apparatuses were built. In order to determine the optimum length of resonant tube and the optimum length of stack, the resonant characteristics of thermoacoustic apparatuses were investigated, The length of resonant tube varies from 400mm to 850mm. The experimental frequency varies from 100Hz to 1000Hz. In case of the second and third harmonics, the maximum temperature difference of open-tube thermoacoustic apparatus is 53$^{\circ}C$ (resonator length: 400mm) and the maximum temperature difference of closed-tube thermoacoustic apparatus is 51$^{\circ}C$ (resonator length: 500mm). In the open-tube thermoacoustic apparatus, the peak efficiency point is about 2%, 55%, 69% in the resonant tube and in the closed-tube thermoacoustic apparatus, the peak efficiency point is about 2%, 41%, 50% in the resonant tube.

Fundamental stuyd on reflection phenomenon of weak pressure-wave from an open end of a pipe (관단으로부터 미소 압력파의 반사에 관한 기초적 연구)

  • Kim, Hui-Dong
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.22 no.5
    • /
    • pp.618-626
    • /
    • 1998
  • This paper describes a series of fundamental studies on reflection and emission of weak pressure waves from an open end of a pipe. Acoustical theories which have been employed in the plane pressure waves inside a pipe are applied to the present study. The objective of the present study is to investigate the reflection or emission coefficient of pressure wave at an open end of a pipe, the length of open end correction, and the directivity characteristics of the pressure waves emitted from the pipe. The results show that the reflection coefficient of pressure wave at an open end and the length of open end correction decrease for the wave length of pressure wave to increase. It is also found that the reflection coefficient for a baffle plate at the exit of pipe is larger than that for no baffle plate.

Thrust and Flow Visualization according to Length of Condenser Section of Open Pulsating Heat Pipe (개방형 구조의 진동형 히트파이프의 응축부 길이에 따른 추력 및 유동 가시화)

  • Minjae Son;Jongwook Choi
    • Journal of the Korean Society of Visualization
    • /
    • v.21 no.3
    • /
    • pp.57-64
    • /
    • 2023
  • An open pulsating heat pipe operates continuously by inflow and outflow fluids through an open-type condenser. The open pulsating heat pipe is a device capable of obtaining the thrust due to the variation of internal pressure during phase change. Therefore, the open pulsating heat pipe is a suitable device to move fluids if the heat source such as waste heat exists. Many numerical studies have not been sufficiently conducted on the open pulsating heat pipe. In this study, the numerical analysis of the open pulsating heat pipe is performed according to the length of the condenser section. The OpenFOAM software is used to obtain the thrust and the flow visualization for the open pulsating heat pipe.

A ROENTGENOCEPHALOMETRIC STUDY ON THE SKELETAL FACTORS IN OPEN-BITE AND DEEP-BITE (개교(開咬)와 과개교합(過蓋咬合)의 골격요소에 관(關)한 두부방사선(頭部放射線) 계측학적(計測學的) 연구(硏究))

  • Park, Jin-Sung
    • The korean journal of orthodontics
    • /
    • v.9 no.1
    • /
    • pp.133-140
    • /
    • 1979
  • The author compared patients showing two extremes of incisor vertical relationship to find out differences in craniofacial morphology which might influence face height and incisor overbite. The subjects consisted of 53 open-bite cases and the same number of deep-bite cases. The results were as follows: 1. On the average, the lower face height was significantly greater in open-bite cases than in deep-bite cases. 2. In open-bite cases, gonin-menton length was significantly greater than in deep-bite cases. In deep-bite cases, anterior cranial base length and posterior cranial base length were significantly greater in open-bite cases. 3. The jaw angle was significantly greater in open-bite cases. 4. The gonion-menton-nasion angle was significantly greater in deep-bite cases. 5. From geometric standpoint, the increase of jaw and joint angle would increase lower face height, but these two showed negative correlation. 6. The sizes of the jaw and joint angle might be factors of open-bite or deep-bite, but these were not the only variables that determined lower face height. 7. In open-bite cases, there was a closer correlationship between lower face height and the other linear measurments than in deep-bite cases. In deep-bite cases, there was a closer correlationship between lower face height and the other angular measurements than in open-bite cases. 8. Considering both linear and angular measurements of facial polygon, all contributed significantly to the lower face height. The nonsignificant variables were jaw and joint angle in open-bite cases, and anterior cranial base length, jaw angle, and joint angle in deep-bite cases.

  • PDF

An Experimental Study on the Characteristics for Open-Tube and Close-Tube Thermoacoustic Effects(1) - The 1st Harmonic (개방관과 밀폐관의 열음향 효과에 관한 하모닉 특성 연구(1) - 1차 하모닉)

  • 송규조;이성노
    • Progress in Superconductivity and Cryogenics
    • /
    • v.4 no.1
    • /
    • pp.129-134
    • /
    • 2002
  • In this study, the experimental open-tube and close-tube thermoacoustic apparatuses were constructed. In order to determine the optimum length of resonant tube, frequency and the optimum length of stack, the resonant characteristics of thermoacoustic apparatuses were investigated, The length of resonant tube varies from 400mm to 850 mm. The experimental frequency varies from 100 Hz to 1000 Hz. In case of first harmonic, the maximum temperature difference of the open-tube thermoacoustic apparatus is 41$^{\circ}C$)resonator length: 500 mm), and the maximum temperature difference of the close-tube thermoacoustic apparatus is 42$^{\circ}C$ (resonator length : 850 mm).

Effects of pile geometry on bearing capacity of open-ended piles driven into sands

  • Kumara, Janaka J.;Kurashina, Takashi;Kikuchi, Yoshiaki
    • Geomechanics and Engineering
    • /
    • v.11 no.3
    • /
    • pp.385-400
    • /
    • 2016
  • Bearing capacity of open-ended piles depends largely on inner frictional resistance, which is influenced by the degree of soil plugging. While a fully-plugged open-ended pile produces a bearing capacity similar to a closed-ended pile, fully coring (or unplugged) pile produces a much smaller bearing capacity. In general, open-ended piles are driven under partially-plugged mode. The formation of soil plug may depend on many factors, including wall thickness at the pile tip (or inner pile diameter), sleeve height of the thickened wall at the pile tip and relative density. In this paper, we studied the effects of wall thickness at the pile base and sleeve height of the thickened wall at the pile tip on bearing capacity using laboratory model tests. The tests were conducted on a medium dense sandy ground. The model piles with different tip thicknesses and sleeve heights of thickened wall at the pile tip were tested. The results were also discussed using the incremental filling ratio and plug length ratio, which are generally used to describe the degree of soil plugging. The results showed that the bearing capacity increases with tip thickness. The bearing capacity of piles of smaller sleeve length (e.g., ${\leq}1D$; D is pile outer diameter) was found to be dependent on the sleeve length, while it is independent on the sleeve length of greater than a 1D length. We also found that the soil plug height is dependent on wall thickness at the pile base. The results on the incremental filling ratio revealed that the thinner walled piles produce higher degree of soil plugging at greater penetration depths. The results also revealed that the soil plug height is dependent on sleeve length of up to 2D length and independent beyond a 2D length. The piles of a smaller sleeve length (e.g., ${\leq}1D$) produce higher degree of soil plugging at shallow penetration depths while the piles of a larger sleeve length (e.g., ${\geq}2D$) produce higher degree of soil plugging at greater penetration depths.

An Experimental Study on the 1st Harmonic Characteristic for open-tube-type and close-tube-type Thermoacoustic Refrigerators (개방관형과 밀폐관형 열음향 냉동기의 1차 하모닉에 관한 특성 연구)

  • 송규조;박종호;고득용;박성제;김효봉;정철진
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2002.02a
    • /
    • pp.189-192
    • /
    • 2002
  • In this study, The experimental open-tube-type and close-tube-type thermoacoustic refrigerator were constructed. The resonant characteristics of a thermoacoustic refrigerator were investigated. In order to determine the optimum resonant tube length and frequency, We changed the length of resonant tube from 400mm to 850mm and the frequency from 100Hz to 1000Hz. In case of first harmonic, the temperature difference of open-tube-type (1/4 wave) refrigerator was $41^{\circ}C$(resonator length :500mm). The temperature difference of close-tube-type (1/2 wave) refrigerator was $43^{\circ}C$(resonator length :850mm). In this experiments, the experimental 1/2 wave refrigerator is slightly cooler than the experimental l/4 wave refrigerator.

  • PDF

A Study on the Aerodynamic Noise of a Supersonic Exhaust Nozzle of Slotted Tube (슬롯관형 초음속 배기노즐의 공력소음에 관한 연구)

  • Lee, Dong-Hoon;Seto, Kunisato
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.24 no.1
    • /
    • pp.132-142
    • /
    • 2000
  • The objective of this study is to experimentally investigate the noise propagating characteristics, the noise reduction mechanism and the performance of a slotted tube attached at the exit plane of a circular convergent nozzle. The experiment is performed through the systematic change of the jet pressure ratio and the slot length under the condition of two kinds of open area ratios, 25% and 51%. The open area ratio calculated by the tube length equivalent for the slot length is defined as the ratio of the total slot area to the surface area of a slotted tube. The experimental results for the near and far field sound, the visualization of jet structures and the static pressure distributions in the jet passing through a slotted tube are presented and explained in comparison with those for a simple tube. The propagating characteristics of supersonic jet noises from the slotted tube is closely connected with the slot length rather than the open area ratio, and its propagating pattern is similar to the simple tube. It is shown that the slotted tube has a good performance to suppress the shock-associated noise as well as the turbulent mixing noise in the range of a limited jet pressure and slot dimension. The considerable suppression of the shock‘associated noise is mainly due to the pressure relief caused by the high-speed jets passing through the slots on the tube. Both the strength of shock waves and the interval between them in a jet plume are decreased by the pressure relief. Moreover, the pressure relief is divided into the gradual and the sudden relief depending upon the open area ratio of the slotted tube. Consequently, the shock waves in a jet plume are also changed by the type of pressure relief. The gradual pressure relief caused by the slotted tube with the open area ratio 25% generates the weak oblique shock waves. On the contrary, the weak normal shock waves appear due to the sudden pressure relief caused by the slotted tube with the open area ratio 51%.