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The multimode light-field camera can capture spatial location and spectral and polarization characteristics of a target simultaneously. There is an aliasing effect, which causes the directly extracted image of a certain filter to include information from other filters. The reconstruction method proposed by Li (Jingzhen Li, thesis of Beihang University, 2015) can improve the accuracy of the polarization images, but the gray values still have gradient variations. In this paper, a method for reconstructing polarization images from the light-field image is proposed along with an aliasing model. Compared with the conventional direct-extraction and Li’s methods, the proposed method can greatly reduce energy loss, and the accuracy of the reconstructed image increases more than fivefold.

In this paper, knock detection and analysis methods of the gasoline engine are applied to a modified kerosene engine. Two kinds of signals, the cylinder pressure signal and the vibration signal, are acquired by a pressure sensor mounted in a spark plug and an accelerometer mounted on the cylinder block separately. Due to the influence of noise, such as cam shocks, piston up-and-down motion, crank rotation and so on, the vibration signal should be processed to extract knock feature. Firstly, FFT, a frequency analysis approach, is used to determine the characteristic frequency range of knock. Then, combining the sampling frequency, the vibration signal is divided into different frequency sub-bands, and the characteristic sub-band of DWT, a time-frequency analysis method, is determined. After that, DWT is applied to extract knock feature from the vibration signal. At last, the knock energy evaluation index is used to judge knock intensity. The reference knock energy is chosen by the researchers, and it is not absolutely suitable for the engine operating condition, so intuitive cylinder pressure signal is applied to supplement for knock judgment.

Growth factors contained in platelet-rich plasma (PRP) can induce osteoblast differentiation in certain studies, whereas in others, osteogenesis of PRP on mandible bone defects has not been proved clinically. The aim of the study was to investigate the effect of autologous PRP on the osteogenic potential of combining bovine porous bone mineral (BPBM) and bio-guide membrane (BGM) in promoting mandible bicortical bony defects in rabbits.

Nano-sized aluminum nitride (AlN) powders were synthesized through a carbothermal reduction nitridation (CRN) route from a sol-gel low temperature combustion precursor. The precursor was precalcined at 600-1200 ℃ and then nitrided at 1400-1550 ℃ for different holding time to obtain AlN powders. During the whole preparation process, the amorphous alumina in the precursors first transformed to γ-Al2O3, then to α-Al2O3, and AlN was obtained through the nitridation of α-Al2O3 with the reduction of carbon. The results show that the appropriate precalcination benefits the activity of precursors and promotes the formation of AlN phase due to the transition of amorphous alumina to γ-Al2O3, and the optimum precalcination temperature is 1000 ℃. The effects of different nitridation parameters on the microstructure of AlN powders were also investigated. By being nitrided at 1500-1550 ℃ for 2 h, the AlN powders present a good distribution and small particle size of 30-90 nm from the precursor precalcinated at 1000 ℃.

This paper have completed the structural design of the GF3.5 25/500, and the cover of the high pressure vessel, flange, the body of the high pressure vessel was stress check, security check, the last combination of pressure tests, air tightness test, Commissioning completion of the three major test the final design.

In this paper, the idea loading and unloading workpiece on catenary based on machine vision has been proposed, for the feature of the hook on catenary, we first used gray-scale transformation, used a variety of edge detection operators to detect the image edge, then combine prewitt edge detection operator and Otsu to segment the hook image, the result shows that this method can extract the image edge of hook effectively, lay a good foundation for loading and unloading workpiece automatically.

800x600 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} Oxidation of carbon is the main problem in magnesia-carbon refractory bricks. Al4SiC4 powder is an excellent antioxidant which has obvious practical significance. It was prepared by vacuum sintering at 1700℃ in vacuum sintering furnace. The effect of Al4SiC4 on the oxidation resistance of magnesia-carbon bricks were investigated at 1500℃. The thickness of decarburized layer of bricks was measured and the oxidized situation of the bricks was examined by XRD, SEM and EDAS. The decarburization layer became thin with adding Al4SiC4 powder. Magnesium alumina spinel (MgAl2O4) was determined to be present by characterization studies on Al4SiC4 added specimens and phase evolution of MgAl2O4 spinel formation were investigated by XRD. The optical microscope and EDAS indicated that the spinel diminished the open pores owing to its volume expansion and formed a protective layer on the surface. The results suggested that the spinel had an excellent effect on the oxidation resistance of bricks. In addition, compared with adding other aluminum-containing antioxidants, the specimens added Al4SiC4 had better stability from high temperature to room temperature.

This paper discusses the basic principle for automatic searching the wheel valve hole based on machine vision. Image acquisition and image processing have been done, and we analyzed the factors that impact the image quality of wheel valve hole. This paper argues that many parameters such as the wheel speed, painting color, the distance between the camera and the valve hole, edge detection operator, and they will affect the quality of the image acquisition and image processing of valve hole.

Combining materials handling and stacking operations, this paper takes the fertilizer bags as the object and studies on the image processing method of the material stacking and segments the stacking image. Using binocular vision technology generates stacking depth image, and the depth data is extracted. It can provide a theoretical basis for the robot to realize the automatic recognition of material stacking.

This paper introducted the machine vision technology into the field of wheel suspension coating, used the industrial cameras for the image information of the wheel center and the valve hole, did the edge detection of the valve hole and the wheel based on visual c++ platform ,making the image feature extraction and analysis, thus completing image recognition of the wheel center and the valve hole, realized hang the wheels to the conveyor of automatically.

According to the features of material bag image, the paper compares an analyzes the detection effects of different edge detection operators detecting material bag image. A new image segmentation method is proposed to combine Sobel edge detection operator and iterative threshold. The method can extract edge information of material bag image efficiently and provide a theoretical basis for the robot automatic recognition of material bags technique.

The paper discusses the major manufacturing processes of vehicle wheels and the current load-unload situation, analyses the structural shape of vehicle wheels, and designs the vehicle wheel gripper. Also the paper studies the image acquisition, image processing and automatic recognition based on the vehicle wheel manufacturing.