This study explores the interaction between spatial configuration,natural mobility,and visual accessibility in exhibition spaces,an area that remains underexplored.By integrating visibility graph analysis(VGA),intelli...This study explores the interaction between spatial configuration,natural mobility,and visual accessibility in exhibition spaces,an area that remains underexplored.By integrating visibility graph analysis(VGA),intelligent agent simulation(IAS),topological analysis,and field observation,the research examines functional layout and accessibility across four museums.Findings indicate that corridors and pathways,second only to exhibition halls,play a crucial role in spatial mobility.Composite layouts(e.g.,circular and L-shaped designs)exhibit superior mean depth and integration,yet connectivity and mean depth demonstrate a nonlinear relationship.Elongated or complex path turns increase cognitive load,complicating navigation,while open passageways promote smoother visitor distribution.Topological analysis effectively identifies optimal nodes,key locations,and path-turn efficiency under accessibility constraints.Visitor dwell time is shaped not only by exhibit content but also by spatial location,entry sequence,and visitor density.Results support the assumption that space syntax models align with realworld visitor flow patterns,yet predictive models fail to fully capture variations in mobility across different timeframes and behavioral contexts.These insights contribute to optimizing museum design for improved visitor experience and spatial efficiency.展开更多
Aiming at the application environment of paddy agricultural machinery with bumpy and undulating changes,the problems affecting the method for steering wheel angle measurement by MEMS gyroscope were analyzed,and a whee...Aiming at the application environment of paddy agricultural machinery with bumpy and undulating changes,the problems affecting the method for steering wheel angle measurement by MEMS gyroscope were analyzed,and a wheel angle measurement method combining Dual-MEMS gyroscope(dual MEMS gyroscope)and RTK-GNSS was designed.The adaptive weighting method was used to fuse the heading angle differentiation of RTK-GNSS,the MEMS gyroscope angle rate,and velocity data,and the rod-arm compensation was performed to accurately obtain the angle rates of the body and steering wheels of agricultural machinery;the difference between the combined angular rate of the steering wheel of the agricultural machinery and the angular rate of the agricultural machinery body was obtained,and the integrator is used to integrate the difference to get the wheel steering angle value,and the Kalman filter was designed to make feedback correction for the integration process of angle calculation to eliminate the errors caused by the gyroscope zero bias,random drift,and gyroscope rod arm effect,and to obtain the accurate value of wheel steering angle.A comparative test with the connecting rod wheel angle sensor was designed,and the results show that the maximum deviation is 4.99°,the average absolute average value is 1.61°,and the average standard deviation is 0.98°.The method in this study and the connecting rod wheel angle sensor were used on paddy farm machinery.The wheel angle measurement deviation of the proposed method and the connecting rod wheel angle sensor was not more than 1°,which is relatively small.It has good stability,speed adaptability,and dynamic responsiveness that meets the accuracy requirements of steering wheel angle measurement for paddy field agricultural machinery unmanned driving and can be used instead of connecting rod angle sensors for unmanned agricultural machinery.展开更多
In this paper, we classify the m-ovoids of finite classical polar spaces that admit a transitive automorphism group acting irreducibly on the ambient vector space. In particular, we obtain several new infinite familie...In this paper, we classify the m-ovoids of finite classical polar spaces that admit a transitive automorphism group acting irreducibly on the ambient vector space. In particular, we obtain several new infinite families of transitive m-ovoids.展开更多
To improve the GNSS receiver’s accuracy,continuity,and stability in measuring the height of agricultural implements,this study proposed a variable-parameter Kalman filter(VPKF)algorithm based on GNSS and acceleromete...To improve the GNSS receiver’s accuracy,continuity,and stability in measuring the height of agricultural implements,this study proposed a variable-parameter Kalman filter(VPKF)algorithm based on GNSS and accelerometer to estimate the height of the implements optimally.The VPKF was verified,and its accuracy was evaluated by parallel rail platform and field tests.From the parallel rail test results,when the GNSS receiver was in real-time kinematic(RTK)positioning and the time delay of differential correction data(TDDCD)was less than or equal to 4 s,the root mean square error(RMSE)of the VPKF estimation was 9.82 mm.The RMSE of the GNSS measurement was 18.85 mm.When the GNSS receiver lost differential correction data within 28 s,the absolute error of VPKF was less than 30 mm,and the RMSE was 16.93 mm.The field test results showed that when the GNSS receiver was in RTK positioning and the TDDCD was less than or equal to 4 s,the RMSE of VPKF estimation was 13.43 mm,and the GNSS measurement was 14.56 mm.When the GNSS receiver lost differential correction data within 28 s,the RMSE of the VPKF estimate was 15.22 mm.These results show that VPKF can optimally estimate implement height with better accuracy.Overall,the VPKF can obtain a more accurate,continuous,and stable height of the implement,and increase the application scenarios of the GNSS receiver to measure the implement height.展开更多
基金funded by the 2024 Individual Academic Enhancement Project of the University Project Pool,entitled“Reproduction and Reconstruction of Historical and Cultural Spaces in the Theoretical Perspective of the Field of Memory(Grant No.24XSC14)”the R&D Program of Beijing Municipal Education Commission(Grant No.SZ202110009003).
文摘This study explores the interaction between spatial configuration,natural mobility,and visual accessibility in exhibition spaces,an area that remains underexplored.By integrating visibility graph analysis(VGA),intelligent agent simulation(IAS),topological analysis,and field observation,the research examines functional layout and accessibility across four museums.Findings indicate that corridors and pathways,second only to exhibition halls,play a crucial role in spatial mobility.Composite layouts(e.g.,circular and L-shaped designs)exhibit superior mean depth and integration,yet connectivity and mean depth demonstrate a nonlinear relationship.Elongated or complex path turns increase cognitive load,complicating navigation,while open passageways promote smoother visitor distribution.Topological analysis effectively identifies optimal nodes,key locations,and path-turn efficiency under accessibility constraints.Visitor dwell time is shaped not only by exhibit content but also by spatial location,entry sequence,and visitor density.Results support the assumption that space syntax models align with realworld visitor flow patterns,yet predictive models fail to fully capture variations in mobility across different timeframes and behavioral contexts.These insights contribute to optimizing museum design for improved visitor experience and spatial efficiency.
基金supported by Science and Technology Innovation 2030–“New Generation Artificial Intelligence”Major Project(Grant No.2021ZD011090202,No.2021ZD011090503)the National Key Research and Development Program of China(Grant No.2021YFD2000602)the National Natural Science Foundation of China(Grant No.32071913,No.32101623).
文摘Aiming at the application environment of paddy agricultural machinery with bumpy and undulating changes,the problems affecting the method for steering wheel angle measurement by MEMS gyroscope were analyzed,and a wheel angle measurement method combining Dual-MEMS gyroscope(dual MEMS gyroscope)and RTK-GNSS was designed.The adaptive weighting method was used to fuse the heading angle differentiation of RTK-GNSS,the MEMS gyroscope angle rate,and velocity data,and the rod-arm compensation was performed to accurately obtain the angle rates of the body and steering wheels of agricultural machinery;the difference between the combined angular rate of the steering wheel of the agricultural machinery and the angular rate of the agricultural machinery body was obtained,and the integrator is used to integrate the difference to get the wheel steering angle value,and the Kalman filter was designed to make feedback correction for the integration process of angle calculation to eliminate the errors caused by the gyroscope zero bias,random drift,and gyroscope rod arm effect,and to obtain the accurate value of wheel steering angle.A comparative test with the connecting rod wheel angle sensor was designed,and the results show that the maximum deviation is 4.99°,the average absolute average value is 1.61°,and the average standard deviation is 0.98°.The method in this study and the connecting rod wheel angle sensor were used on paddy farm machinery.The wheel angle measurement deviation of the proposed method and the connecting rod wheel angle sensor was not more than 1°,which is relatively small.It has good stability,speed adaptability,and dynamic responsiveness that meets the accuracy requirements of steering wheel angle measurement for paddy field agricultural machinery unmanned driving and can be used instead of connecting rod angle sensors for unmanned agricultural machinery.
基金supported by National Natural Science Foundation of China (Grant No. 12171428)the Sino-German Mobility Programme M-0157Shandong Provincial Natural Science Foundation (Grant No. ZR2022QA069)。
文摘In this paper, we classify the m-ovoids of finite classical polar spaces that admit a transitive automorphism group acting irreducibly on the ambient vector space. In particular, we obtain several new infinite families of transitive m-ovoids.
基金funded by the Laboratory of Lingnan Modern Agriculture Project(Grant No.NT2021009)National Natural Science Foundation of China(Grant No.32071913No.32101623).
文摘To improve the GNSS receiver’s accuracy,continuity,and stability in measuring the height of agricultural implements,this study proposed a variable-parameter Kalman filter(VPKF)algorithm based on GNSS and accelerometer to estimate the height of the implements optimally.The VPKF was verified,and its accuracy was evaluated by parallel rail platform and field tests.From the parallel rail test results,when the GNSS receiver was in real-time kinematic(RTK)positioning and the time delay of differential correction data(TDDCD)was less than or equal to 4 s,the root mean square error(RMSE)of the VPKF estimation was 9.82 mm.The RMSE of the GNSS measurement was 18.85 mm.When the GNSS receiver lost differential correction data within 28 s,the absolute error of VPKF was less than 30 mm,and the RMSE was 16.93 mm.The field test results showed that when the GNSS receiver was in RTK positioning and the TDDCD was less than or equal to 4 s,the RMSE of VPKF estimation was 13.43 mm,and the GNSS measurement was 14.56 mm.When the GNSS receiver lost differential correction data within 28 s,the RMSE of the VPKF estimate was 15.22 mm.These results show that VPKF can optimally estimate implement height with better accuracy.Overall,the VPKF can obtain a more accurate,continuous,and stable height of the implement,and increase the application scenarios of the GNSS receiver to measure the implement height.
