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A planar measurement approach is presented to obtain the radiation pattern, by which rotation operations can be removed or reduced for a source with narrow and divergent viewing angle, respectively. The Étendue conservation is applied to derive the intensity distribution relationship between planar and spherical surfaces, which is further used for the radiation feature measurement on planar systems. As an indirect approach, sampling position distribution and measurement sensitivity is then discussed. Four application scenarios of the method are proposed and experimentally studied, including: 1D, 3D wireframe, pattern reconstruction for Monte Carlo ray-tracing planar data and 3D pattern estimation for luminaires. 1D radiation pattern obtained by classical goniophotometer method is employed as an evaluation standard, and experiments indicate that the results agree well between the two approaches. Therefore, the planar measurement can be applied as an alternative or supplementary method of the goniophotometer to test angle-dependent attributes of sources.

MPS (Moving Particle Semi-Implicit) method is an effective method to solve the simulation of large-deformation free surface fluid flow. In order to improve the stability and accuracy of the MPS method, this paper proposes a collision model between fluid particles. The collision model assumes that the collisions between fluid particles are completely elastic collisions and follow the law of conservation of momentum and energy. The improved MPS method is used for the fluid simulation of two-dimensional and three-dimensional fluid dam break model. The simulation results show that the improved MPS algorithm has good stability, the calculation results are in better agreement with the experimental data, and it has a wider range of adaptability. The improved MPS method is more suitable for the simulation of large-deformation free surface fluid flow.

The existing modeling methods for geomagnetism aided inertial navigation and their applicability are analyzed. Due to the requirement of high precision and local application for geomagnetic parameter modeling, a modeling method based on fast Fourier series is introduced to model the local geomagnetic measurements. Then by contrasting research between Fourier fitting modeling and the representative Taylor polynomial modeling, the former has been proved to be of higher fitting precision. The feasibility and effectiveness of the Fourier series model have been showed with the modeling result. At last, from the result of a simulation on a 15′×15′ geomagnetic anomaly data, we can see that the mean square error (MSE) of the Fourier series modeling is less than 0.2283nT. So the modeling problem for regional high precision in geomagnetism aided inertial navigation has been effectively solved.

Interference and anti-jamming of communication systems are key areas of electromagnetic compatibility research. Because of the restrictions of the complexity of communications systems, it is difficult to accurate analyze system characteristics by model and simulation. This paper presents a hybrid simulation method (a digital behavioral simulation and in-the-loop simulation analysis) to simulate effects of anti-jamming receiver. After achieving an accurate model of receiver, we realized analysis of the additive narrowband interference, additive modulation interference and band selective. Practice proved that the hybrid simulation method is accurate. It can achieve rapid analysis and verification for an unknown communication system.

Some samples of ash were taken from a Semi-dry FGD dealing with sinter gas which was released from iron industry. Scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectrometer (FTIR) were employed to identify the samples in order to investigate their physical and chemical characteristics. The result shows that: this kinds of semi-dry FGD ash is stable, and its characteristics have no significant change in the dry environment at room temperature. The contents of CaSO 3 and SO 3 in the semi-dry FGD ash from iron industry are higher than those from power plant gas. The semi-dry FGD ash has smooth surface, loose structure and contain many small holes. It is consist of CaSO 3 , CaSO 4 , CaCO 3 , corundum and mullite, et al. The diameter of the ash is distribute from 3.42 mu m to 13.77 mu m, the mean particle diameter is about 4.18 mu m and specific surface area is about 7.94 m 2 /g.

We present a general approach to speeding up a family of multi-relational data mining algorithms that using ID propagation to obtain the information needed for building decision tree classifier from relational database. Preliminary results of our experiments suggest that the proposed method can yield 1-2 orders of magnitude reductions in the running time of such algorithms without any deterioration in the accuracy of results. The proposed modifications enhance the applicability of decision tree algorithms to significantly relational databases that would otherwise be not feasible in practice.

A multi-relational association rule mining algorithm with guidance of the user is proposed in this paper. A tuple ID propagation approach is used to solve the association rule mining with multiple database relations directly, and introduces the concept of the user's guidance in this paper. The approach has improved user's satisfaction with the mining result. Compared with the traditional algorithms, it improves the accuracy and supports multi-relational databases directly, so its running time is less than that of the multi-relational association rule mining methods based on ILP.