• Title/Summary/Keyword: Inclined Plane

Search Result 207, Processing Time 0.025 seconds

Defects Length Measurement Using an Estimation Agorithm of the Camera Orientation and an Inclination Angle of a Laser Slit Beam (레이저 슬릿 빔의 경사각과 카메라 자세 추정 알고리듬을 이용한 벽면결함 길이측정)

  • Kim, Young-Hwang;Yoon, Ji-Sup;Kang, E-Sok
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.8 no.1
    • /
    • pp.37-45
    • /
    • 2002
  • A method of measuring the length of defects on the wall and restructuring the defect image is proposed based on the estimation algorithm of a camera orientation, which uses the declination angle of a laser slit beam. The estimation algorithm of the horizontally inclined angle of CCD camera adopts a 3-dimensional coordinate transformation of the image plane where both the laser beam and the original image of the defects exist. The estimation equation is obtained by using the information of the beam projected on the wall and the parameters of this equation are experimentally obtained. With this algorithm, the original image of the defect can be reconstructed as an image normal to the wall. From the result of a series of experiments, the measuring accuracy of the defect is measured within 0.5% error bound of real defect size under 30 degree of the horizontally inclined angle. The proposed algorithm provides the method of reconstructing the image taken at any arbitrary horizontally inclined angle as the image normal as the wall and thus, it enables the accurate measurement of the defect lengths by using a single camera and a laser slit beam.

구치(臼齒)의 근원심(近遠心) 경사도(傾斜度)에 관(關)한 두부방사선계측학적(頭部放射線計測學的) 연구(硏究)

  • Chio, Byung Taik;Yang, Won Sik
    • The korean journal of orthodontics
    • /
    • v.14 no.1
    • /
    • pp.151-160
    • /
    • 1984
  • This study was designed to get the informations of the mesiodistal axial inclinations of the posterior teeth and of the relationships between these and other angular measurements of facial bony structures in normal occlusion and malocclusion groups using lateral roentgenocephalograms. The subjects consisted of 73 normal occlusions (31 males 42 females), 38 Class II Division 1 malocclusions (17 males 21 females) and 47 Class III malocclusions (19 males 28 females). The findings of this study are as follows : 1. In mandible, the posterior teeth axes of Class II Division 1 malocclusion group were inclined more mesially and those of Class III malocclusion group were inclined more distally than normal occlusion group. In maxilla, Class II Division 1 malocclusion group showed more distal inclination and Class III malocclusion group showed more mesial inclinaton of 1st, 2nd premolars and more distal inclination of 1st, 2nd molars than those of the normal occlusion group. 2. There was a tendency for teeth axes to maintain nearly the same inclination in relation to occlusal plane irrespective of various OMA and OPA in each group. 3. F M A, P M A and O P A were the largest in Class II Division 1 malocclusion group and O M A, GoA were the largest in Class 111 malocclusion group. 4. There were high correlationships between mandibular teeth inclinations related to mandibular plane and 4 angular measurements except OPA, and between maxillary teeth inclinations related to palatal plane and OPA.

  • PDF

Analysis of Photoelastic Stress Field Around Inclined Crack Tip by Using Hybrid Technique (하이브리드 기법에 의한 경사균열 팁 주위의 광탄성 응력장 해석)

  • Chen, Lei;Seo, Jin;Lee, Byung-Hee;Kim, Myung-Soo;Baek, Tae-Hyun
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.34 no.9
    • /
    • pp.1287-1292
    • /
    • 2010
  • In this paper, a hybrid technique is presented. First, the isochromatic fringe data of a given set of points are calculated by the finite element method and are used as input data in complex variable formulations. Then the numerical model of the specimen with a central inclined crack is transformed from the physical plane to the complex plane by conformal mapping. The stress field is analyzed and the mixed-mode stress intensity factors are calculated for this complex plane. The stress intensity factors are calculated by the finite element method as well as by a theoretical method and compared with each other. In order to conveniently compare these values with each other, both actual and regenerated photoelastic fringe patterns are multiplied by a factor of two and sharpened by digital image processing.

A Study of the Twisting and Extrusion Process of the Product with Involute Helical Fin from the Round Billet by the Upper Bound Analysis (상계해법에 의한 원형빌렛으로부터 인볼루트 헬리컬핀을 가진 제품의 비틀림 압출가공법에 관한 연구)

  • 박대윤;진인태
    • Transactions of Materials Processing
    • /
    • v.10 no.4
    • /
    • pp.302-310
    • /
    • 2001
  • The twisting and extrusion process of the product with involute helical fin from the round billet is developed by the upper bound analysis. The twisting of extruded product is caused by the twisted inclined die surface connecting the die enterance section and the die exit section linearly. In the analysis, the internal shear surface is defined as the curved twisted plane from the twisting of die surface and the shear work is calculated by the consumption of shear energy. The increase rate of angular velocity is determined by the minimization of plastic work. The angular velocity of die exit can be controlled by the land length and the length of inclined die. The alular velocity assums to be increased linearly by the axial distance from the die enterance to the die exit. The results of the analysis show that the angular velocity of the extruded product increases with the die twisting angle, the reduction of area, and decreases with the die length, the friction constant.

  • PDF

Prediction of Mean Cutting Force in Ball-end Milling using 2-map and Cutting Parameter (Z-map과 절삭계수를 이용한 볼엔드밀의 평균절삭력 예측)

  • 황인길;김규만;주종남
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1995.10a
    • /
    • pp.179-184
    • /
    • 1995
  • A new cutting parameter is defined in the spherical part of ball end-mill cutter. A series of slot cutting experiments were carried out to obtain the cutting parameter. The cutter contact area is expressed as the grid posiotion in the cutting plane using Z map. The cutting forces in each grid are calculated and saved as force map, prior to the average cutting forces calculation. The cutting force, in the arbitrary cutting area, can be easily calculated by summing up the cutting forces of the engaged grid in the force map. This model was verified in the inclined surface cutting by cutting test of a cylindrical part.

  • PDF

Analysis of Maximum Solar Radiation on Inclined Surfaces in Korea (국내 최대 경사면일사량 분석)

  • Jo, Dok-Ki;Yun, Chang-Yeol;Kim, Kwang-Deuk;Kang, Young-Heack
    • 한국태양에너지학회:학술대회논문집
    • /
    • 2009.04a
    • /
    • pp.3-7
    • /
    • 2009
  • The amount of incident rays over inclination according to direction has been widely utilized as important data in installing solar thermal systems. To optimize the incident solar radiation, the slope, that is the angle between the plane surface in question and the horizontal, and the solar azimuth angles are needed for these solar thermal systems. This is because the performance of the solar thermal systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized solar thermal systems will be provided for designers and employees working in the solar collector related industries.

  • PDF

FLOW-INDUCED FORCES ON AN INCLINED SQUARE CYLINDER (기울어진 정방형 실린더에 작용하는 유체력)

  • Yoon, Dong-Hyeog;Yang, Kyung-Soo;Choi, Choon-Bum
    • Journal of computational fluids engineering
    • /
    • v.14 no.3
    • /
    • pp.9-15
    • /
    • 2009
  • Numerical investigation has been carried out for laminar flow past an inclined square cylinder in cross freestream. In particular, inclination of a square cylinder with respect to the main flow direction can cause sudden shift of the separation points to other edges, resulting in drastic change of flow-induced forces on the cylinder such as Strouhal number (St) of vortex shedding, drag and lift forces on the cylinder, depending upon the inclination angle. Collecting all the numerical results obtained, we propose contour diagrams of drag/lift coefficients and Strouhal number on an Re-Angle plane. This study would be the first step towards understanding flow-induced forces on cylindrical structures under a strong gust of wind from the viewpoint of wind hazards.

Analysis of Maximum Solar Radiation on Inclined Surfaces for the Installation of Solar Thermal Systems in Korea Using the Optimum Installation Angle (국내 태양열시스템 설치를 위한 시스템 최적 설치각 산출을 통한 최대 경사면일사량 분석)

  • Jo, Dok-Ki;Kang, Young-Heack
    • Journal of the Korean Solar Energy Society
    • /
    • v.29 no.2
    • /
    • pp.47-54
    • /
    • 2009
  • The amount of incident rays over inclination according to direction has been widely utilized as important data m installing solar thermal systems. To optimize the incident solar radiation, the slope, that is the angle between the plane surface in question and the horizontal, and the solar azimuth angles are needed for these solar thermal systems. This is because the performance of the solar thermal systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized solar thermal systems will be provided for designers and employees working in the solar collector related industries.

Finite element analyses of the stability of a soil block reinforced by shear pins

  • Ouch, Rithy;Ukritchon, Boonchai;Pipatpongsa, Thirapong;Khosravi, Mohammad Hossein
    • Geomechanics and Engineering
    • /
    • v.12 no.6
    • /
    • pp.1021-1046
    • /
    • 2017
  • The assessment of slope stability is an essential task in geotechnical engineering. In this paper, a three-dimensional (3D) finite element analysis (FEA) was employed to investigate the performance of different shear pin arrangements to increase the stability of a soil block resting on an inclined plane with a low-interface friction plane. In the numerical models, the soil block was modeled by volume elements with linear elastic perfectly plastic material in a drained condition, while the shear pins were modeled by volume elements with linear elastic material. Interface elements were used along the bedding plane (bedding interface element) and around the shear pins (shear pin interface element) to simulate the soil-structure interaction. Bedding interface elements were used to capture the shear sliding of the soil on the low-interface friction plane while shear pin interface elements were used to model the shear bonding of the soil around the pins. A failure analysis was performed by means of the gravity loading method. The results of the 3D FEA with the numerical models were compared to those with the physical models for all cases. The effects of the number of shear pins, the shear pin locations, the different shear pin arrangements, the thickness and the width of the soil block and the associated failure mechanisms were discussed.

Testing for validity of isometric muscle endurance test as an abdominal muscular endurance evaluation methods (복근 지구력 평가 도구로서 등척성 수축 후 버티기 방법의 타당성 비교 검증)

  • Park, Soon-Tae;Hur, Sung-Hoon;Lee, Jang-Kyu;Lee, Jong-Sam
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.2
    • /
    • pp.815-827
    • /
    • 2014
  • The current study was undertaken to verify appropriateness of muscle endurance test at three different angles ($30^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$) of isometric contraction position, and to sought valid and reliable testing method that provide an alternative to sit-ups. Total 92 young and healthy subjects (68 males and 24 females) were recruited, and the following results were obtained. 1. A low correlations in males, but a high correlations in females was found when the comparisons were made between aerobic and muscle endurance capability. 2. Measuring tolerance time, by using isometric contraction was showed a significant correlation with the repetition numbers of sit-ups. 3. The highest correlation was found at 40 inclined degrees of plane, and the lowest correlation was drawn from 50 inclined degrees of plane. Based on these results, it was concluded that measuring tolerance time during maintaining an isometric contraction at 40 inclined degrees of plane is a valid and effective tool for measuring abdominal muscle endurance, and it can be used as an alternative way of sit-up, which potentially risky for inducing many back-associated injuries. Further studies need to be undertaken to determine for optimal angles, that can safely be applied for people of various age groups and physical conditions.