Theoretical and experimental study of scour depth by submerged water jet

The characteristics and working principles of the impinging by submerged water jet are analyzed, and the relevant mathematical model is optimized based on Rajaratnam’s theoretical and experimental study. A new mathematical model is constructed by adding an important parameter called impinging angle. A new experiment is designed according to the working conditions of various impinging distances and angles. In combination with the experiment data and with the use of the curve fitting method, the functional relationship between the impinging distance and angle as well as the coefficient C4 is obtained. The experiment results show that the scour depth decreases as impinging distance increases, followed by a trend from decline to rise before falling again; those two turning points occur within the range of 20d–25d. The scour depth constantly increases with rising impinging angle, and the maximum and minimum increasing ranges can reach 180% and 50%, respectively, with the impinging angle increasing from 40° to 90°.

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Method of Estimating the Foundation Settlement under Different Working Conditions through Settlement Measurement

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.744-746.527 ◽

2015 ◽

Vol 744-746 ◽

pp. 527-530

Author(s):

Ai Min Liu ◽

Ai Jun ZhuGe

Keyword(s):

Working Conditions ◽

Curve Fitting ◽

Back Analysis ◽

Foundation Settlement ◽

Analysis Method ◽

Large Area ◽

Soft Foundation ◽

Fitting Method ◽

Service Load ◽

Curve Fitting Method

In the large-area soft foundation reinforcement project, the loading process is relatively complicated and the preloading load is not consistent with the service load in most cases; thus the conventional settlement curve fitting method cannot nicely predict the post-construction settlement of foundation under the service load. The back analysis method can be used to obtain the calculation parameters, so the settlement and consolidation conditions under various different loads at different time can be calculated and the foundation settlement hereby can be estimated exactly.

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The Experimental Study on Modal Parameters Identification for Motorman-HP20 Robot

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.201-202.561 ◽

2012 ◽

Vol 201-202 ◽

pp. 561-564

Author(s):

Gang Zhang ◽

Hai Bo Huang ◽

Ting Zhang

Keyword(s):

Experimental Study ◽

Orthogonal Polynomials ◽

Dynamic Characteristics ◽

Curve Fitting ◽

Parameters Identification ◽

Modal Parameters ◽

The Poor ◽

Fitting Method ◽

Modal Parameters Identification ◽

Curve Fitting Method

The dynamic characteristics of light-weighted structure are more important due to its flexible property. In this paper, the experiment of modal analysis for Motorman-HP20 robot is carried out. The method of one location for response and multi-locations for excitation are applied in the experiment. The orthogonal polynomials curve fitting method is used for modal parameters identification. The first six order modal parameters are obtained. The results show that the structure of L-shape arm may be re-designed due to the modal shapes due to severe vibration of L-shape arm in modal frequencies of some prior orders and the poor base frequency.

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Experimental Study of Thermal Conductivity of Carbon Fiber Reinforced Cement-Based Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.502.212 ◽

2012 ◽

Vol 502 ◽

pp. 212-216 ◽

Cited By ~ 1

Author(s):

Ya Dong Bian ◽

Ran Hai

Keyword(s):

Thermal Conductivity ◽

Experimental Study ◽

Carbon Fiber ◽

Functional Relationship ◽

Fiber Reinforced ◽

Experiment Data ◽

Air Bubble ◽

Fitting Method ◽

Reinforced Cement ◽

Carbon Fiber Reinforced

This paper studies the carbon fiber weight influencing on the thermal conductivity of carbon fiber reinforced cement-based composites. Experiment results show that the thermal conductivity decreases with the increase of carbon fiber weight. It is because that the air bubble results from the proceeding when the carbon fiber adds into cement-based composites. When the carbon fiber weight is less than 1.0%(by mass), the thermal conductivity decreases significantly. And when the weight is more than 1.0%, the decreasing tendency starts to slow down. Based on the experiment data, the functional relationship between the thermal conductivity and carbon fiber weight is obtained by using the fitting method.

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Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System Performance

Metrology and Measurement Systems ◽

10.2478/v10178-012-0033-8 ◽

2012 ◽

Vol 19 (2) ◽

pp. 381-394

Author(s):

José Pereira ◽

Octavian Postolache ◽

Pedro Girão

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Measurement System ◽

Curve Fitting ◽

System Performance ◽

Redox Potentials ◽

Voltage Sweep ◽

Gaussian Curve ◽

Fitting Method ◽

Curve Fitting Method

Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System PerformanceThis paper presents a voltammetric segmented voltage sweep mode that can be used to identify and measure heavy metals' concentrations. The proposed sweep mode covers a set of voltage ranges that are centered around the redox potentials of the metals that are under analysis. The heavy metal measurement system can take advantage of the historical database of measurements to identify the metals with higher concentrations in a given geographical area, and perform a segmented sweep around predefined voltage ranges or, alternatively, the system can perform a fast linear voltage sweep to identify the voltammetric current peaks and then perform a segmented voltage sweep around the set of voltages that are associated with the voltammetric current peaks. The paper also includes the presentation of two auto-calibration modes that can be used to improve system's reliability and proposes the usage of a Gaussian curve fitting of voltammetric data to identify heavy metals and to evaluate their concentrations. Several simulation and experimental results, that validate the theoretical expectations, are also presented in the paper.

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