• Title/Summary/Keyword: volume estimate

Search Result 871, Processing Time 0.033 seconds

Relationship between Growth Factors and Spectral Characteristics of Satellite Imagery in Korea

  • Park, Ji-Hoon;Ma, Jung-Lim;Nor, Dae-Kyun;Kim, Chan-Hoi;Hwang, Hyo-Tae;Jung, Jin-Hyun;Kim, Sung-Ho;Jo, Hyeon-Kook;Lee, Woo-Kyun;Chung, Dong-Jun
    • Journal of Forest and Environmental Science
    • /
    • v.24 no.3
    • /
    • pp.165-169
    • /
    • 2008
  • This study attempts to analyze the relationship between forest volume and age based on 5th NFI data and spectral characteristics of satellite imagery using ASTER sensor in Korea. Forest stand volume and age had the negative correlation with the spectral reflectance in all of the band (Blue, Green, Red, SWIR). With increasing of stand volume and age, spectral reflectance decrease. The spectral reflectance of band1 showed the highest correlation between stand volume and spectral reflectance among the VNIR wavelength. The spectral reflectance band 1, 2 (visible wavelength) and stand age have high correlation compared to other bands. The correlation coefficients between forest volume and vegetation indices have low relationship. This result indicates that the reflectance of blue band may be important factor to improve the potential of optical remote sensing data to estimate forest volume and age.

  • PDF

Automatic Calculation of Interior Volume of Refrigerator by Hole Filling Algorithm (분해모델과 구멍 메움 알고리즘을 이용한 냉장고 내부 용적의 자동 계산)

  • Park, Raesung;Fu, Jianhui;Jung, Yoongho;Park, Mingeun
    • Korean Journal of Computational Design and Engineering
    • /
    • v.22 no.1
    • /
    • pp.59-69
    • /
    • 2017
  • Internal capacity of a refrigerator is an important indicator for design and purchasing criteria. The components facing the internal space may have holes or gaps between parts. In traditional way, design engineers manually remodeled the parts to fill the holes and the gaps for enclosed boundary of the internal space. Then they calculated internal volume by subtracting the assembly of parts from its enclosing volume. However, filling holes and gaps is not an automated process requiring a plenty of labor and time. In this research, we have developed a voxel-based method to estimate the internal volume of a refrigerator automatically. It starts transforming all components facing the interior space into voxels and fills all holes and gaps automatically by the developed hole-filling algorithm to form a completely closed boundary of the assembly. Then, it identifies the boundary voxels that are facing to the internal voxels with any part of the component. After getting the intersection points between the boundary voxels and the surfaces of components, it generates the boundary surface of triangular facets with the intersection points. Finally, it estimates the internal volume by adding volume of each tetrahedron composed of a triangle of boundary surface and an arbitrary point.

Spline Surface Approximation for Computing Pit Excavation Volume with the Free Boundary Conditions

  • Jaechil Yoo;Lee, Seung-Hoon;Mun, Du-Yeoul
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2002.04a
    • /
    • pp.229-238
    • /
    • 2002
  • The calculation of earthwork plays a major role in plan or design of many civil engineering projects, and thus it has become very important to improve the accuracy of earthwork calculation. In this paper, we propose an algorithm of finding a cubic spline surface with the free boundary conditions, which interpolates the given three dimensional data, by using B-spline and an accurate method to estimate pit-excavation volume. The proposed method should be of interest to surveyors especially concerned with accuracy of volume computations. We present some computational results showing that our proposed method provides good accuracy.

  • PDF

A Study on the Discharge Pressure Ripple Characteristics of Variable Displacement Vane Pump (가변용량형 유압 베인펌프의 토출압력맥동 특성 연구)

  • 장주섭;김경훈
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.11 no.3
    • /
    • pp.106-114
    • /
    • 2003
  • The pressure ripple in the delivery port is caused by flow ripple, which is induced by variation of pumping chamber volume. The other reason is the reverse flow from the outlet volume produced by pressure difference between pumping chamber and outlet volume, when the pumping chamber is connected with the outlet volume. In this study, a mathematical model is presented for analyzing discharge pressure ripple, which includes vane detachment, cam ring movement , and fluid inertia effects in V-groove in the side plate. From the analysis and experiment, it was found that V-groove on the side plate, coefficient of spring supporting the cam ring, and average discharge pressure are the main factors of discharge pressure ripple in variable displacement vane pump. The theoretical results, provided in this study, were well agreed with experimental results. The analytical model to estimate the magnitude of pressure ripple in this study is expected to be used f3r the optimal design of the variable displacement vane pump.

A Study on Computing Pit Excavation Volume by Terrain Surface Approximation (지형곡면해석에 의한 토공량 계산에 관한 연구)

  • 문두열;정범석
    • Journal of Ocean Engineering and Technology
    • /
    • v.16 no.6
    • /
    • pp.37-43
    • /
    • 2002
  • The calculation of earthwork plays a major role in the plan or design phase of many civil engineering projects, such as seashore reclamation; and thus, it has become very important to improve upon its accuracy. There have been common drawbacks to earlier methods of ground profiling, such as dialing with sharp corners or the grid points of any tow straight lines. In this paper, we prepose an algorithm for finding a terrain surface using the natural boundary conditions and the both direction spline method, which interpolates the given three-dimensional data by using spline. As a result of this study, the algorithm of the proposed two methods to estimate pit excavation volume should provide a better accuracy than Spot height, Chambers, Chen, or Lin method. Also, the mathematical model mentioned offers maximum accuracy in estimating the volume of a pit excavation.

A New Algorithm to Calculate the Optimal Inclination Angle for Filling of Plunge-milling

  • Tawfik, Hamdy
    • International Journal of CAD/CAM
    • /
    • v.6 no.1
    • /
    • pp.193-198
    • /
    • 2006
  • Plunge milling is the fastest way to mill away large volumes of metal in the axial direction. The residual volume (inaccessible volume by the plungers) is minimized when selecting a specific direction of filling. This direction is known as the optimal inclination angle for filling of the plunged area. This paper proposes a new algorithm to calculate the optimal inclination angle of filling and to fill the plunged area with multi-plungers sizes. The proposed algorithm uses the geometry of the 2D area of the shape that being cutting to estimate the optimal inclination angle of filling. It is found that, the optimal inclination angle for filling of the plunged area is the same direction as the longer width of the equivalent convex polygon of the boundary contour. The results of the tested examples show that, the residual volume is minimized when comparing the proposed algorithm with the previous method.

An Experimental Study on the Engineering Properties of HPFRCC According to Kinds, Shapes and Volume Fraction of Fibers (섬유의 종류, 형상 및 치환율에 따른 HPFRCC의 공학적 특성에 관한 실험적 연구)

  • 김영덕;조봉석;김재환;김규용;최경렬;김무한
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2003.05a
    • /
    • pp.59-62
    • /
    • 2003
  • Kinds, shapes and fraction ratios of fibers have influence on properties of HPFRCC(High-Performance Fiver Reinforced Cementitious Concrete ) like bending strength, strain capacity and fracture toughness. For example, hydrophilic fibers have different chemical bond strength from hydrophobic fibers, fiber shapes influence on fiber pull-out and rupture, and fiber volume fraction influence on bending strength. In this study, to estimate influences of kinds, shapes and fraction ratios of fibers, we make HFRCC with 3 kind of fiber in various volume fraction of fiber and compare cracking, bending strength and fracture toughness. As the results, bending strength of HPFRCC was increased as fiber volume fraction was Increase and fiber tensile strength was increase, and strain capacity and fracture toughness of HFRCC was higher in fiber pull-out fracture than in fiber rupture fracture. And HFRCC showing pseudo strain hardening has higher fiber reinforce efficiency than others.

  • PDF

A Study on the Pit Excavation Volume Using Cubic B-Spline

  • Mun, Du-Yeoul
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
    • /
    • v.5 no.1
    • /
    • pp.40-45
    • /
    • 2002
  • The calculation of earthwork plays a major role in the planning and design phases of many civil engineering projects, such as seashore reclamation; thus, improving the accuracy of earthwork calculation has become very important. In this paper, we propose an algorithm for finding a cubic spline surface with the free boundary conditions, which interpolates the given three-dimensional data, by using B-spline and an accurate method to estimate pit-excavation volume. The proposed method should be of interest to surveyors, especially those concerned with accuracy of volume computations. The mathematical models of the conventional methods have a common drawback: the modeling curves form peak points at the joints. To avoid this drawback, the cubic spline polynomial is chosen as the mathematical model of the new method. In this paper, we propose an algorithm of finding a spline surface, which interpolates the given data, and an appropriate method to calculate the earthwork. We present some computational results that show the proposed method, of the Maple program, provides better accuracy than the method presented by Chen and Lin.

  • PDF

Study on the Volume Fraction Optimization of Functionally Graded Heat-Resisting Composites (기능경사 내열 복합재의 체적분율 최적화에 관한 연구)

  • Jo, Jin-Rae;Ha, Dae-Yul
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.25 no.6
    • /
    • pp.988-995
    • /
    • 2001
  • Functionally graded materials(FGMs) are highlighted to be suitable for high temperature engineering due to their continuous distribution of material properties. In this paper, an optimal design is executed for determining the optimal material volume distribution pattern that minimizes the steady-state thermal stress of FGM heat-resisting composites. The interior penalty function method and the golden section method are employed as optimization techniques while the finite element method is used for thermal stress analysis. Through numerical simulations we suggest the volume fraction distributions that considerably improve initial thermal stress distributions.

Spline Surface Approximation for Computing Pit Excavation Volume with the Free Boundary Conditions

  • Yoo, Jae-Chil;Lee, Seung-Hoon;Mun, Du-Yeoul
    • Korean Journal of Geomatics
    • /
    • v.2 no.1
    • /
    • pp.25-29
    • /
    • 2002
  • The calculation of earthwork plays a major role in plan or design of many civil engineering projects, and thus it has become very important to improve the accuracy of earthwork calculation. In this paper, we propose an algorithm for finding a cubic spline surface with the free boundary conditions, which interpolates the given three dimensional data, by using B-spline and an accurate method to estimate pit-excavation volume. The proposed method should be of interest to surveyors especially concerned with accuracy of volume computations. We present some computational results showing that our proposed method provides good accuracy.

  • PDF