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The accurate and rapid measurement of the roadheader pose is the premise and foundation of intelligent heading in coal mine roadway. The existing cantilever roadheader pose measurement has the problem of non-absolute pose measurement, low measurement precision, complex arrangement, or only a few pose parameters being measured. The measurement can not meet the intelligent heading requirement. In order to solve the above problems, based on the pose measurement method of the cantilever roadheader based on laser target tracking, a pose measurement system of cantilever roadheader based on laser target tracking is designed. The system consists of a laser tracking device and a laser target. The laser tracking device is arranged behind the roadway, emits laser to the laser target arranged on the cantilever roadheader fuselage, and tracks the movement of the laser target. By solving the conversion matrix between coordinate systems such as laser tracking device, laser target, roadheader and roadway, six absolute pose parameters such as heading direction position, offset, height, deviation angle, pitch angle and roll angle can be measured. The full parameter real-time measurement of absolute pose of cantilever roadheader in roadway coordinate system is realized. The error influence factors of the system are analyzed, and the error distribution law is obtained by simulation. With the increase of heading distance, the pose measurement error of roadheader changes within a certain range. The measurement errors of offset and height increase linearly. Within the measurement range of 5-80 m, the measurement errors of the deviation angle, pitch angle and roll angle of the roadheader are less than 1.4, 1, 0.03° respectively. The measurement error of the heading direction position is less than 5 mm, and the measurement errors of offset and height are less than 20 mm. Using the crawler robot chassis, an experimental system for pose measurement is built. The pose measurement experiment is carried out in the simulated roadway. The results show that the measurement errors of the heading direction position, offset and height are less than 5 mm. The measurement error of the deviation angle is less than 1°. The measurement error of the pitch angle is less than 0.6°. And the measurement error of the roll angle can be ignored. The results are consistent with the simulation results, which proves the reliability of the system.

The simulation of fuel composition requires coupled calculations of neutron transport and burnup. It is generally assumed that the neutron flux density and cross-sections remain constant within a burnup step. However, when there are strong absorber poisons present, the reaction rates of the absorbers change too rapidly over time, necessitating extremely fine step sizes to ensure computational accuracy, which in turn leads to low computational efficiency. As a type of accident tolerant fuel (ATF), fully ceramic micro-encapsulated (FCM) fuel is a promising new type of nuclear fuel. Accelerated algorithms for burnup calculations of FCM fuel containing gadolinium isotopes have been developed based on the ALPHA code, including the projected predictor–corrector (PPC), the log-linear rate (LLR), and the high-order predictor–corrector (HOPC) methods (including CE/LI, CE/QI, LE/LI, and LE/QI). The performances of different algorithms under the two forms of Gd2O3 existence were analyzed. The numerical results show that the LE/QI method performs the best overall. For Gd2O3 existing in both forms, the LE/QI algorithm can maintain accuracy with a burnup step size of up to 1.0 GWd/tU, keeping the infinite multiplication factor kinf within 100 pcm, and it exhibits high accuracy in simulating the atomic number densities of Gd-155 and Gd-157 throughout the burnup process. [ABSTRACT FROM AUTHOR]

Utilizing observed wind speed and direction data from observation stations near the Taiwan Strait and ocean buoys, along with forecast data from the EC model, GRAPES_GFS model, and PanGu weather prediction model within the same period, RMSE, MAE, CC, and other parameters were calculated. To comparatively evaluate the forecasting performance of the PanGu weather prediction model on the sea surface wind field near the Taiwan Strait from 00:00 on 1 June 2023, to 23:00 on 31 May 2024. The PanGu weather prediction model is further divided into the ERA5 (PanGu) model driven by ERA5 initial fields and the GRAPES_GFS (PanGu) model driven by GRAPES_GFS initial fields. The main conclusions are as follows: (1) over a one-year evaluation period, for wind speed forecasts with lead times of 0 h to 120 h in the Taiwan Strait region, the overall forecasting skill of the PanGu weather prediction model is superior to that of the model forecasts; (2) different initial fields input into the PanGu weather prediction model lead to different final forecast results, with better initial field data corresponding to forecast results closer to observations, thus indicating the operational transferability of the PanGu model in smaller regions; (3) regarding forecasts of wind speed categories, the credibility of the results is high when the wind speed level is ≤7, and the PanGu weather prediction model performs better among similar forecasts; (4) although the EC model's wind direction forecasts are closer to the observation field results, the PanGu weather forecasting model also provides relatively accurate and rapid forecasts of the main wind directions within a shorter time frame. [ABSTRACT FROM AUTHOR]