Applied Mechanics and Materials Vols. 530-531

Abstract: This paper introduces the main measuring methods for sediment concentration of runoff, including the traditional methods, such as ultrasonic method, infrared method, γ-ray method, as well as the newly proposed methods, such as capacitance method , specific heat method. But each of these methods has their limitations. X-ray measuring method for sediment concentration of runoff is good at the measuring accuracy and range, it is sure that X-ray method can open up a new path for measuring sediment concentration of runoff.

Abstract: Wavelength and other factors have a deep influence on temperature measurement system based on CCD image sensor. Deviations between measurement values sometimes are large. In order to reduce error, the temperature outputs in different wavelength combinations do have multi-sensor correlation properties in point of colorimetric temperature measurement system view. The colorimetric temperature measurement algorithm based on real-time adaptive weighted is put forward by such performance index that minimum of standard deviation. According to measured value of each sensor, we will find out the corresponding weights in adaptive manner. And discuss the statistical properties of the estimated standard deviation. Estimation unbiasedness is proved. The algorithm has the following advantages .A much smaller amount of calculation, without any a priori knowledge, only relying on the output of each sensor. All of these make temperature estimation be optimal, measurement accuracy and the real-time performance of the system are improved. Theoretical analysis and experimental results show that the colorimetric temperature measurement algorithm based on the real-time adaptive weighted improves obviously when comparing with the traditional means algorithm in measurement accuracy.

Abstract: Magnetic guidance drilling technology is use of magnetic guidance instrument measuring the distance between the signal source and the location of the instrument, and it is used to control the well trajectory to connect or parallel the target layer. And it is an effective supplement of the existing steering drilling technology. At present, the magnetic guidance drilling technology is mainly applied to drill horizontal wells in pairs for the super heavy recovery, CBM horizontal connected wells, underground soluble minerals, relief well and so on. This paper introduces the situation of the magnetic guidance drilling technology.

Abstract: The orientation estimation is a critical technique in inertial sensor based motion capture systems. One challenge of the orientation estimation is that it suffers from the acceleration interference due to body segment motion, especially when the acceleration interference is significant. In this paper, we propose a quaternion based orientation estimation algorithm using unscented Kalman filter. In the algorithm, the acceleration interference is taken as an element of the state vector and estimated in the algorithm together with the orientation quaternion, knowing that the acceleration interference can be predicted based on the rotational angular velocity. The experiments were conducted using both computer simulation and in real-world motion scenarios. Both experimental results have shown the effectiveness of the proposed orientation estimation algorithm.

Abstract: Air bubble size distribution in a laboratory flotation cell was investigated by using of image analysis technology in this paper. Results showed that it was feasible to determine the air bubble size according to image analysis software. For a porous media-aerated flotation cell, bubble size was dependent on poles size of porous media. Furthermore, operating parameters of the cell could affect the size. Mean bubble diameters increased with increasing of air flow rate. In contrast, it decreased when adding deinking agent. Its decreasing with increasing pulp flow rate under given conditions illustrated the fact that proper turbulence strength at the inlet of air bubbles was favorable for reducing bubble size. Gas holdup increased with increasing air flow rate to some extent, but it had a peak value. Gas holdup would rise obviously when deinking agent existed. An efficient approach to enhancing bubble surface area flux was to increase air flow rate and keep small bubble size at the same time.

Abstract: One photoelectrical test method and system were optimal developed for messuring the optical performances of some scintillation crystals. The theoretical Critical Focal Length of the measurement system is firstly deduced and used in order to make the most of both X-ray photons and the effective area of the scintillation crystal panel. Furthermore, coaxial cable ordered is used to replace the carried wire to weaken power noise. Finally, a low-pass filter with 35Hz upper limit cut-off frequency is designed to reduce spike interference of high-frequency noise. Experiments are successfully done to comprehensive test the spectral response, conversion efficiency and spatial resolution of some scintillators, and the results show that the presented system in this paper is helpful to test the scintillator properties.

Abstract: A method to evaluate surface defects, size of metal plate was put forward base on infrared thermography and time sequence images features. Put 45# steel plate as the object, firstly, time-sequence images in cooling process was got based on infrared thermography technology; Secondly, according to the change features of gray value in normal area and defect area of time sequence images, an identification was made to tell in which image the different factors exists. Finally, combined statistical differences between normal and defect area with image processing techniques to achieve the defect area evaluation. On the basis of laboratory studies, trials of 45# steel sheet were carried out in laboratory and the expected goals were reached. Proposed method enables the average relative errors for each evaluated defect area are less than 7 percent. which can provide a useful reference for the evaluation of defect area of infrared nondestructive testing field.

Abstract: To accurately estimate the projectile ballistic trajectory, where the real impact point can not be identified in case of indirect firing, a 3D tracking radar with Doppler is used during the first portion of projectile trajectory to estimate the projectile attitude and angular motion during flight, and hence; compute the impact point using a nonlinear six-degree-of-freedom 6-DOF trajectory model. A numerical study is done to investigate the effect of the flight stability of a 105mm artillery projectile on the length of Doppler radar data needed to accurately estimate the projectile impact point. A discrete time transfer matrix method DTTM-4DOF is used to estimate the in-flight projectile angular motion using Doppler radar measurements. Simulated Doppler radar data are generated using the 6-DOF model including the projectile initial disturbance problem.

Abstract: The in-situ acoustic measurement is very important in geoacoustics and underwater acoustics. An in-situ acoustic instrument of Attenuation Array is used to measure sound speed of water to examine the different data analysis methods. Based on the first arrival cycle (FAC) judgment method, point judgment based data analysis method (PJDAM) and cross correlation based data analysis method (CCDAM) have the similar results of sound speed as 1479.4±0.6 and 1480.5±2.1 m/s respectively in a wide range of measurement frequency changing from 100kHz to 300kHz, which is very close to the standard sound speed of 1480 m/s of water measured in-situ with CTD. The analysis method will be useful in in-situ measurement of seafloor sediment.

Abstract: There are currently various algorithms with mass spectrometry in phosphorylation identification. Some quality control methods have also been proposed. However, a detailed comparative analysis among various methods has not been reported. In the paper, based on the theory of forward-reverse databases searching, we compare current major algorithms in database searching and identification i.e Mascot and Sequest, and compare various aspects and methods of algorithms in site assessment. We propose an effictive quality control method. Our result shows that this method can ensure the quality of identification and identify more phosphorylation sites.