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This paper aims to achieve the accurate prediction of box girder deformation in SCS-enhanced PSC continuous box girder bridges. To this end, the authors proposed a box girder deformation prediction model based on unequal interval grey model (UIGM) and residual composite correction (RCC). Firstly, the tension forces of cables and the deformation data of box girder were regarded as the time sequence and the original unequal interval sequence, respectively, and the UIGM was constructed to predict the box girder deformation. Secondly, the sine function was constructed on the average features of the residual sequence waveform, and the periodic sequence function was generated by harmonic transform. The two functions were employed to extract the implicit periodic information and overcome the limitation of the UIGM (i.e., the UIGM only generates the change rate of a single index). Finally, the Markov chain method was adopted to treat the random fluctuations and further enhance the prediction accuracy and adaptability of the model. Then, the proposed UIGM-RCC was applied to predict the box girder deformation of Dongming Huanghe River Highway Bridge and forecast the settlement of a building mentioned in previous research. The results show that the proposed model can reflect the exact periodicity and random fluctuations of box girder deformation in SCS-enhanced PSC continuous box girder bridges. The research findings provide a meaningful reference for improving deformation prediction accuracy in SCS-enhanced structures.

According to the basic principle and method of cut flowers preservation, orthogonal experimental design was carried out to study the preservation effect of domestic vase solution made of sugar, aspirin and lemon juice on Gladiolus cut flowers. The results showed that J7 containing 20 g L−1 white granulated sugar and 28 ml L−1 lemon juice could significantly prolong the vase life of Gladiolus cut flowers, promote the opening of florets, improve the daily ornamental value, increase the fresh weight of spray, maintain the water balance and water content of petals, delay the decomposition of protein and the production of malondialdehyde, which was the best domestic vase solution.

In view of the traditional saliency detection method gets imprecise and vague region boundary, so that the detected object is not connected, the paper proposes image visual saliency feature extraction based on multi-scale tensor space. The method introduces the tensor space, using multiple low-level image features to construct the tensor space, after reducing dimension the image space structure and correlation features are preserved, making the detected object connective, which is beneficial to feature extraction and target detection, at last the features uncertainty weights are calculated for total saliency feature fusion. The experimental results show that the algorithm of feature extraction proposed in this paper is closer to the real object and achieves better results.

Focused light field camera can be used to measure three-dimensional (3-D) temperature field of a flame because of its ability to record intensity and direction information of each ray from flame simultaneously. This work aims to develop a suitable geometric calibration method of focused light field camera for 3-D flame temperature measurement. A modified method based on Zhang's camera calibration is developed to calibrate the camera and the measurement system. A single focused light-field camera is used to capture images of bespoke calibration board for calibration in this study. Geometric parameters including intrinsic (i.e., camera parameters) and extrinsic (i.e., camera connecting with the calibration board) of the focused light field camera are calibrated to trace the ray projecting onto each pixel on CCD (charge-coupled device) sensor. Instead of using line features, corner point features are directly utilized for the calibration. The characteristics of focused light field camera including one 3-D point corresponding to several image points and matching main lens and microlens f-numbers, are used for calibration. Results with a focused light field camera are presented and discussed. Preliminary 3-D temperature distribution of a flame is also investigated and presented.

A non-contact measurement method, namely an electrostatic probe, for particle charging characteristics determination is introduced in the paper. Using the probe, the charging trends of the pulverized bituminous coal in a dense phase pneumatic conveying system at low pressure were investigated for gas superficial velocities in a range of 6-10 m/s and particle concentrations in a range of 128-230 kg/m3. The observations indicated that increasing the coal particles concentration leads to an increase in charge level of the pulverized coal particles and then a decrease, and a peak of the charge level is experienced in the range of 150-160 kg/m3. The charges carried by the coal particles increase with the increase of gas superficial velocity in the pipeline, and then reach saturation values.

Inversion of droplet size distribution in two-phase flow from light scattering has been considered involved because it is in general reduced to the solution of Fredholm integral equation of the first kind that was always ill-posed. By using the Rosin-Rammler distributiona priori as the particulate size distribution model in the liquid-gas two-phase flow, a method via the solution of a two-parameter nonlinear programming problem to determine the droplet size distribution has been developed. A measurement system based on the technique is designed and applied in the shock test of blades of steam turbine. 100-hours continuous monitoring of the droplets in the liquid-gas two-phase flow of 8.0 Pa and 120 °C was performed and the details of the experiments are given out. It is shown that the technique is simple and efficient for in-situ real time measuring droplets in the liquid-gas two-phase flow.

The Electrical Capacitance Tomography (ECT) system is applied to identify the flow regime of gas-solid flows in horizontal pipeline with 10mm inner-diameter in a pulverized coal dense-phase pneumatic conveying experimental setup at the pressure up to 4.0MPa and the solid-gas ratio up to 11.73kg/kg. 8-electrode thick-pipeline and small-diameter ECT sensor applied in high pressure is fabricated, and the pipeline thickness is 5 mm. For the purpose of analyzing the effect of pipeline thickness on ECT sensor, radius-electrode ratio is defined as the ratio of inner and outer radius of pipeline. The rules of 8-electrode sensor parameters such as capacitance, capacitance change, and change rate of capacitance and sensitivity map are discussed by ANSYS and Matlab, which are combined to simulate sensor characteristic. With the increase of radius-electrode ratio, the effect of pipeline thickness on capacitances of four typical inter-electrode pairs is much different. LBP algorithm is adopted to reconstruct the images of stratified flow, core flow and annular flow with different radius-electrode ratios. Simulation results show that image error under high radius-electrode ratio is small, and the image reconstructed from stratified flow is better than the ones from core flow and annular flow. Finally, the experimental result of 8-electrode ECT with thick pipeline sensor, which is used on the pulverized coal dense-phase pneumatic conveying experimental setup, is given.

In order to analyze electromagnetic environment in present high voltage converter station, measurements in SMX converter station were carried out. Results indicate that power frequency electric field and magnetic field at many measuring points are beyond the basic national standards, and necessary shielding measures should be taken, in addition, exposure time in the converter station should be minimized. Noise interference and wireless interference in the converter station is below the limit.

This paper introduces a new high accuracy turning Multiple measurement and control high accuracy turning Multiple measurement and control system developed by authors recently. It mainly consists of microcomputer, multichannel capactive probes, precision positioning and measurement equipment, (compensation micro-servo device) and high accuracy optical digital length gauge. The functions of the system include: on- line measurement of inside and outside diameter, length, and feed control of the turning tool. Positional accuracy of 0.03 μm, feed resolution of 0.1μ and feed accuracy of 0.5 μm are achieved.

Hydro-servo valve is one of very improtant part in hydro-cintrol system. Becauce the limiting of its manufacturing accuracy, some serious influence can be brought into all of the cintrol system, therefore make its control accuracy bad.