scholarly journals Determination of the Sediment Carrying Capacity Based on Perturbed Theory

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Zhi-hui Ni ◽  
Qiang Zeng ◽  
Wu Li-chun
Keyword(s):  
Carrying Capacity ◽  
Influencing Factor ◽  
Least Square Method ◽  
Least Square ◽  
New Method ◽  
Linear Regression Method ◽  
Average Flow Velocity ◽  
New Formula ◽  
Sediment Carrying Capacity

According to the previous studies of sediment carrying capacity, a new method of sediment carrying capacity on perturbed theory was proposed. By taking into account the average water depth, average flow velocity, settling velocity, and other influencing factors and introducing the median grain size as one main influencing factor in deriving the new formula, we established a new sediment carrying capacity formula. The coefficients were determined by the principle of dimensional analysis, multiple linear regression method, and the least square method. After that, the new formula was verified through measuring data of natural rivers and flume tests and comparing the verified results calculated by Cao Formula, Zhang Formula, Li Formula, Engelung-Hansen Formula, Ackers-White Formula, and Yang Formula. According to the compared results, it can be seen that the new method is of high accuracy. It could be a useful reference for the determination of sediment carrying capacity.

X-ray Diffractometric Determination of Lattice Misfit Between γ and γ' Phases in Ni-Base Superalloys

1988 ◽  
Vol 32 ◽  
pp. 365-375 ◽  
Author(s):  
Katsumi Ohno ◽  
Hirosi Harada ◽  
Toshihiro Yamagata ◽  
Michio Yamazaki ◽  
Kazumasa Ohsumi
Keyword(s):  
Lattice Misfit ◽  
Least Square Method ◽  
Least Square ◽  
X Rays ◽  
Deconvolution Method ◽  
X Ray ◽  
Window Functions ◽  
Profile Fitting ◽  
Overlapping Peaks

AbstractThe lattice misfits between γ and γ' phases in Ni-base superalloys (single crystal) were accurately determined for filings of specimens by using both a conventional X-ray tube focusing diffractometer(CXRFD) and a synchrotron-radiation parallel beam X-ray diffractometer (SRPXRD). All reflection peaks measured with the CXRFD were in a cluster of overlapping peaks because of the very small differences in the lattice parameters of both phases and the instrumental broadening due to X-ray optics including the spectral distribution of Xray source such as CuKα doublet. The deconvolution method was applied to remove the instrumental broadening from the peaks measured with the CXRFD. The window functions for the deconvolution method were calculated from CuKα doublet reflection of Si standard by a nonlinear least-square method.The instrumental broadening of SRPXRD was much smaller than that of CXRFD since the monochromatic X-rays produced single peak profiles and constant profile shape over a wide 2θ range. A profile fitting with a pseudo-Voigt function was used to determine 2θ angles to 0.0005 deg. for the synchrotron powder data. The peak angle and shape reflected from γ' phases in γ-matrix and those fron electrochemically extracted γ'-phase were significantly different.

Critical Assessment of the Least Square Error Method Used in Derivation of Morison’s Force Coefficients

1994 ◽  
Vol 116 (1) ◽  
pp. 1-6 ◽  
Author(s):  
G. Najafian ◽  
R. Burrows
Keyword(s):  
Critical Assessment ◽  
Least Square ◽  
New Method ◽  
Statistical Moments ◽  
Circular Cylinders ◽  
Wave Forces ◽  
Lower Intensity ◽  
Maximum Correlation ◽  
Error Method

The least square error (LSE) method is frequently used in determination of Morison’s coefficients from the analysis of measured wave forces on circular cylinders. It will be proved in this paper that Morison’s coefficients determined from the LSE method always lead to predicted forces which have smaller variances (2nd-order statistical moments) than those of the measured forces. In other words, it is proved that predicted forces from this method are of lower intensity compared to the measured forces, and hence can be unconservative. A new method, termed the maximum correlation (MC) method, has been introduced. This method has all the advantages of the LSE method, but leads to predicted forces whose variances are equal to those of the measured forces.

scholarly journals Numerical evaluation of the modulus of longitudinal elasticity in structural round timber elements of the Eucalyptus genus

2011 ◽  
Vol 31 (5) ◽  
pp. 1007-1014 ◽  
Author(s):  
André L. Christoforo ◽  
Túlio H. Panzera ◽  
Fabiano B. Batista ◽  
Paulo H. R. Borges ◽  
Francisco A. R. Lahr
Keyword(s):  
Inverse Analysis ◽  
Numerical Evaluation ◽  
Least Square Method ◽  
Least Square ◽  
Analysis Method ◽  
The Finite Element Method ◽  
Eucalyptus Citriodora ◽  
Inverse Analysis Method ◽  
Round Timber

Currently, the standards that deal with the determination of the properties of rigidity and strength for structural round timber elements do not take in consideration in their calculations and mathematical models the influence of the existing irregularities in the geometry of these elements. This study has as objective to determine the effective value of the modulus of longitudinal elasticity for structural round timber pieces of the Eucalyptus citriodora genus by a technique of optimization allied to the Inverse Analysis Method, to the Finite Element Method and the Least Square Method.

Study on Ship Form Technical and Economic Evaluation DS Based on Interactive MCDM

2006 ◽  
Author(s):  
Sang Song ◽  
Li-Hua Jun
Keyword(s):  
Decision Making ◽  
Analytical Hierarchy Process ◽  
Accurate Result ◽  
Multiple Criteria Decision Making ◽  
Least Square Method ◽  
Least Square ◽  
New Method ◽  
Decision Systems ◽  
Complex Decision ◽  
Hierarchy Process

A new method of interactive Multiple Criteria Decision Making (MCDM) is presented. In order to settle the problem that in the cases for the ship designers sometimes it is difficult to make a decision when facing so complex ship form schemes. The conventional AHP (Analytical Hierarchy Process) is adopted, but it mostly depends on the designer’s subjective and leads to the systematic error. The new method can obtain the accurate result with the rigid least square method as a tool, making full use of the AHP and the objective information entropy, which reflects the inherent attribute. When applied in the practice, it is proved to be effective, practical and dependable for future ships’ complex Decision Systems (DS).

The Analysis and Discussion of Sediment Transport Capacity Formula

2012 ◽  
Vol 188 ◽  
pp. 259-263 ◽  
Author(s):  
Wei Yi Zhang ◽  
Gui Ying Lu ◽  
Xi Shan Pan
Keyword(s):  
Diffusion Equation ◽  
Carrying Capacity ◽  
Sediment Concentration ◽  
Two Dimensional ◽  
Transport Capacity ◽  
Sediment Transport Capacity ◽  
Sediment Data ◽  
New Formula ◽  
Sediment Carrying Capacity ◽  
High Application

Combined with the equilibrium condition, the formula of vertical average sediment concentration has been derived from the vertical two-dimensional suspended sediment diffusion equation. Based on analyzing and comparing two hydrodynamic formulas, a new formula of sediment carrying capacity has been deduced. Some river and inshore sediment data has been collected to validate the formula and find that the new formula has higher accuracy and applicability comparing with the two hydrodynamic formulas, it shows that the new formula has a high application value.

A REVIEW OF FORMULAE FOR AVERAGING PHYSICAL QUANTITIES (APPLICATION TO CALCULATION OF THE AVERAGE RADIUS OF TUBES)

2007 ◽  
Vol 31 (2) ◽  
pp. 235-242
Author(s):  
I. A. Stepanov
Keyword(s):  
Traditional Method ◽  
Time Dependent ◽  
New Method ◽  
Arbitrary Form ◽  
Average Radius ◽  
Average Value ◽  
Average Flow Velocity ◽  
Flow Through ◽  
New Formula ◽  
Physical Quantities

A new method for averaging physical quantities is discovered. It is shown that the traditional method of finding the average value of a physical quantity gives the wrong results when calculating the average radius of a tapering tube, the average flow velocity in the tube and the volume of liquid flow through the tapering tube. The new method of averaging gives the correct results. The new formula is applicable to many other processes, for example, for calculating the flow through tubes of arbitrary form or with time-dependent radius. At present, a neutral radius is used which leads to big discrepancies.

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