Applied Mechanics and Materials Vols. 513-517

Abstract: Photon correlation technique is an effective method for measuring the particle size of sub-micron particles and nanoparticles. This technology has a good prospect and commercial value. Photon correlator is used in photon correlation spectroscopy experiment to gain the photon correlation function. In order to obtain the accurate values of the photon correlation, efficient and accurate photon correlator must be designed. This paper presents one kind of photon correlator implemented by FPGA. The programming language used is Verilog HDL. The software design and system simulation are completed in the integration circumstance of ISE. The photon correlator can meet the different requirements of photon correlation.

Abstract: The disadvantages of domestic and oversea shadow image edge detection algorithms are analyzed. A novel shadow detection algorithm based on edge growing and rough set theory and subsequent solution is proposed. We describe how to detect image edge using condition attribution of rough set in this paper. Also, the method of thinning and connection for shadow edge using edge growing from the edge nodes is proposed. As can be seen from the experimental analysis, the method we proposed has better performance in edge detection and image segmentation.

Abstract: Emulsion droplets or multi-emulsion droplet formation was important for functional materials synthesizing by microfluidic. To obtain tunable monodisperse droplets with millimeter scale, the flow regime in co-flowing channels was divided by numerical simulation. A typical co-flowing model was created using finite volume method, and the VOF (volume of fluid) muti-phase model was selected. Then, droplets were produced by changing the velocity ratio under the dripping regime. Compared to the experimental value of droplet diameter, theoretical and numerical absolute error was below 60 % and 15 %, separately. Greet agreement of diameter changing tendency was found in simulation and experiment.

Abstract: The relative light output of liquid scintillator based on p-xylene (PX) was measured in this paper. The setup for testing on light output was clearly displayed. The results showed that the light yield increased as the addition of the second solute p-bis (o-methylatyryl)- benzene (bis-MSB). Bis-MSB moves the maxmun of fluorescence emission spectra of liquid scintillator from 365nm to 425nm, which is the most sensitive region for the PMT, so the possibility of self-absorption and the loss of light output could be reduced to some extent.

Abstract: Micro springs are often served in the fuzes MEMS-based safe and arm systems as force and energy transmission elements, which are critical to guarantee the fuze safe and arm systems' safety in normal time and proper function after launching. While the micro springs are easy to get buckled under pressure thus influence the normal function, to avoid that, the relationships between the critical buckling pressure and the structural parameters were taken into consideration in the design process. Taking the S-shaped micro spring as example, models were built using modeling software Inventor and eigenvalue buckling analysis was performed with the FEM (finite-element method) software ANSYS, hence the relationships between the critical buckling pressure and the structural parameters of the micro spring in certain conditions were obtained.

Abstract: In this paper, we propose an efficient way to produce an initial transposed matrix for two point clouds, which can effectively avoid the drawback of local optimism caused by using standard Iterative Closest Points (ICP)[ algorithm when matching two point clouds. In our approach, the correspondences used to calculate the transposed matrix are confirmed before the point cloud forms. We use the depth images which have been carefully target-segmented to find the boundaries of the shapes that reflect different views of the same target object. Then each contour is affected by curvature scale space (CSS)[ method to find a sequence of characteristic points. After that, our method is applied on these characteristic points to find the most matching pairs of points. Finally, we convert the matched characteristic points to 3D points, and the correspondences are there being confirmed. We can use them to compute an initial transposed matrix to tell the computer which part of the first point cloud should be matched to the second. In this way, we put the two point clouds in a correct initial location, so that the local optimism of ICP and its variations can be excluded.

Abstract: Based on the Timoshenko beam theory, the dynamics model of a spindle system is constructed. The Young’s modulus of the material and the stiffness of bearing are considered as random variables for a Monte Carlo simulation about the spindle system’s first nature frequency. The simulation results shows that the statistical attribute of these parameter introduce variation to the systems dynamics property. The reliability of avoiding the spindle resonance is then calculated.

Abstract: With the increasing requirements of the machining accuracy of CNC machine tools, the impact of thermal deformation is growing. Thermal error compensation technology can predict and compensate the thermal errors in real-time, and improve the machining accuracy of the machine tool. In this paper, the research objects of thermal error compensation is expanded to the volumetric error of the machine tool, the volumetric error modeling of a three-axis machine tool is fulfilled and a compensator is developed for the compensation experiment, which provides scientific basis for the improvement of the machining accuracy.

Abstract: Generally, the indexable inserts carry out work with arc transition edges, which have a wiping effect on surface under processing and reduce the roughness of the surface. [ However, existing literatures lack research on the forming of arc transition edge surface. In this paper, the unified mathematical model and forming methods of different arc transition edge surfaces were presented, which can be used for other forming process. The mathematic models deduced would lay the most important foundation for manufacturing indexable inserts automatically. The models presented could also be extended for study on some complicated transition surfaces. Finally, the simulation was done and the result verified the theoretical derivation.

Abstract: This is a research paper on heat exhaust capacity and cutting force during the process with CBN quill design. This study tested and evaluated heat exhaust capacity in processing in the form of CBN quill and examined failures by thermal transformation in the processing and problems of tool life. It applied Taguchi method to solve problems in the reduction of processing load and thermal impact evaluation of the periphery by quill design and aimed to design an ideal tool form.