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GNSS relative positioning stochastic model reflects the noise level of observation data, in the process of baseline processing, reasonable stochastic model can improve the precision of calculating. Beidou navigation system (BDS) consists of three kinds of satellite: Geosynchronous Earth Orbit satellite (GEO), Medium Earth Orbit satellite (MEO) and Inclined Geosynchronous Satellite Orbit (IGSO). Due to the difference of orbits, it should be distinguished when select stochastic model for the three kinds of satellite. In this paper, the three kinds of satellite are assigned different weight based on posteriori root mean square error (RMS) of Beidou zero-difference phase observation combined with elevation angle stochastic model, and based on BDS baseline processing software, the conclusion is verified by experiment with 79.4 km baseline data of seven days. The experiment result shows that it can improve the precision and daily repeatability of BDS baseline result as the biggest, least and middle weight are assigned to IGSO, MEO and GEO respectively when processing data of BDS; the baseline result of BDS processed by the BDS baseline processing software are compared with baseline result of GPS processed by Bernese software, it shows that the difference of the two results is less than 1 cm in plane direction and less than 2.6 cm in up direction.

Pulsed power research for military and civil applications has been conducted at the China Academy of Engineering Physics (CAEP) for more than 50 years. The pulsed power research activities include development of pulsed power components, such as different kinds of high-voltage switches, series of pulsed power sources and pulsed X-ray machines, high-current accelerators for $Z$ -pinch and flash X-ray radiography, as well as medical application and electromagnetic launch. The most recent progress of pulsed power research at CAEP will be presented.

With the rapid development of MEMS technique and manufacturing technology, the Attitude Heading Reference System (AHRS) based on Micro-electromechanical Systems Inertia Measure Unit (MEMSIMU) has gained more and more popularity in civil field, for example, the small unmanned aircraft, wearable devices and precision agriculture system and so on. But, because of the noise of MEMSIMU and the influence of vehicle’s dynamics, the precision of vehicle’s attitude given by AHRS can’t meet the requirements of precision agriculture system, aiming at providing effective attitude information for the agricultural machineries, the high-precision and reliable positional information given by Global Navigation Satellite System (GNSS) has been used to revise the attitude calculated by AHRS and estimate the compensate parameters of MEMSIMU online. By using the BMI160 sensor module and Hi-Target V30 GNSS receiver, and using Trimble APX15’s solution as reference, the testing experiments are provide to compare the performance of the conventional single AHRS algorithm and the Tightly-coupled GNSS/AHRS EKF fusion algorithm, the experimental results show that the proposed GNSS/AHRS EKF fusion algorithm can effectively inhibit the accumulation of the angular error and achieve state attitude output.

Rolling force for strip casting of 1Cr17 ferritic stainless steel was predicted using theoretical model and artificial intelligence. Solution zone was classified into two parts by kiss point position during casting strip. Navier-Stokes equation in fluid mechanics and stream function were introduced to analyze the rheological property of liquid zone and mushy zone, and deduce the analytic equation of unit compression stress distribution. The traditional hot rolling model was still used in the solid zone. Neural networks based on feedforward training algorithm in Bayesian regularization were introduced to build model for kiss point position. The results show that calculation accuracy for verification data of 94.67% is in the range of ±7.0%, which indicates that the predicting accuracy of this model is very high.

A time-resolved measurement system of spot size for X-ray sources was constructed by coupling a gated CCD camera with a fast scintillator crystal. The spot size of the high-energy pulsed X-ray source from the Dragon-Ⅰ linear induction accelerator was measured at 10 ns intervals, and a curve of spot size versus time was obtained. An LYSO crystal array with a pixel size of 0.78 mm was also designed and tested in X-ray field, and primary experimental results show the array can be used for time-resolved spot size diagnosis of the high energy X-ray source and significantly improve the spatial resolution of X-ray images.

Spot size is one of the parameters to characterize the performance of a radiographic X-ray source. It determines the degree of blurring due to magnification directly. In recent years, a variety of measurement methods have been used to diagnose X-ray spot size at Laboratory of Accelerator Physics and Application (LAPA). Computer simulations and experiments showed that using a rolled-edge to measure the spot size are more accurate, and the intensity distribution of X-ray source was obtained by a device with a square aperture. Experimental and simulation results on a flash X-ray source at our laboratory are presented and discussed in this paper. In addition, a new method for time resolved diagnostics of X-ray spot size is introduced too.

In the experiment of flash-radiography, the quality of acquired image strongly depends on the focal size of the x-ray source spot. A variety of techniques based on imaging of pinhole, slit and rollbar are adopted to measure the focal spot size of the Dragon-I linear induction accelerator. The image of pinhole provides a two-dimensional distribution of the x-ray spot, while those of slit and rollbar give a line-spread distribution and an edge-spread distribution, respectively. The spot size characterized by full-width at half-maximum and that characterized by the LANL definition are calculated for comparison., Comment: 8 pages, 6 figures

In this paper, the entity-connector and non-entity-connector of design feature are defined and the connector is divided into two classes. The P/T net-based hierarchy structure model of the component-connector design feature and the energy flowing P/T net model of the primitive mechanism are built up. The product model is mathematically described from the perspectives of the function, design feature, attribute and their relationships. Then the P/T net-based hierarchy structural model is applied to represent the conceptual product, and the energy flowing P/T net is established to simulate the working status of the conceptual product.

Assessment index system is constructed based on online advertising publisher viewpoint and this complete assessment index system consists of three class indicators. Maximum deviation method based on deviation degree and possibility degree of multi-attribute decision making was improved, and the exact data and interval data were integrated together, the problem of hybrid multi-attribute decision making are solved. At last, through a real example, the proposed method is objectively and evaluation results are reliable.

In order to adapt automatic transmission system to the complex running conditions of tracked vehicle, the primary principle of fuzzy intelligent shift control of tracked vehicle is proposed and the simulation model of tracked vehicle drive train are established, based on human-vehicle-road closed loop system of vehicle steering parameter, road surface status and driver manipulating information. An intelligent fuzzy shift control system composed of a basic fuzzy shift strategy and a fuzzy modification module is developed to improve dynamic conditions and cross-country maneuverability. The simulation result shows that the fuzzy shift strategy can improve the shift quality of a tracked vehicle under varying driving conditions and avoid shift cycling effectively. Therefore the intelligent fuzzy shift strategies are effective.