This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapi...This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapidly-exploring Random Trees*(Q-RRT*)algorithm.A cost inequality relationship between an ancestor and its descendants was derived,and the ancestors were filtered accordingly.Secondly,the underwater gravity-aided navigation path planning system was designed based on the DSFS algorithm,taking into account the fitness,safety,and asymptotic optimality of the routes,according to the gravity suitability distribution of the navigation space.Finally,experimental comparisons of the computing performance of the ChooseParent procedure,the Rewire procedure,and the combination of the two procedures for Q-RRT*and DSFS were conducted under the same planning environment and parameter conditions,respectively.The results showed that the computational efficiency of the DSFS algorithm was improved by about 1.2 times compared with the Q-RRT*algorithm while ensuring correct computational results.展开更多
This study explores the application of parallel algorithms to enhance large-scale sorting, focusing on the QuickSort method. Implemented in both sequential and parallel forms, the paper provides a detailed comparison ...This study explores the application of parallel algorithms to enhance large-scale sorting, focusing on the QuickSort method. Implemented in both sequential and parallel forms, the paper provides a detailed comparison of their performance. This study investigates the efficacy of both techniques through the lens of array generation and pivot selection to manage datasets of varying sizes. This study meticulously documents the performance metrics, recording 16,499.2 milliseconds for the serial implementation and 16,339 milliseconds for the parallel implementation when sorting an array by using C++ chrono library. These results suggest that while the performance gains of the parallel approach over its serial counterpart are not immediately pronounced for smaller datasets, the benefits are expected to be more substantial as the dataset size increases.展开更多
模块化多电平换流器(modular multi-level converter,简称MMC)的子模块均压有利于降低开关损耗,消除直流侧环流,被广泛应用于高压直流(high-voltage direct current,简称HVDC)输电系统中.基于快速选择排序算法,对MMC进行分组排序研究,...模块化多电平换流器(modular multi-level converter,简称MMC)的子模块均压有利于降低开关损耗,消除直流侧环流,被广泛应用于高压直流(high-voltage direct current,简称HVDC)输电系统中.基于快速选择排序算法,对MMC进行分组排序研究,在快速选择排序基础上设计改进快速选择排序,以时间复杂度为目标进行优化.基于子模块电容电压上限和直流电压波动范围提出双电压限原则,并对子模块进行分组,以降低开关损耗.通过在SIMULINK上进行仿真试验,论证改进快速排序算法和分组双电压限排序的可行性.结果显示:改进快速选择算法比传统排序算法速度提高将近8倍;基于双电压限的分组方法可以有效降低开关频率.展开更多
基金the National Natural Science Foundation of China(Grant No.42274119)the Liaoning Revitalization Talents Program(Grant No.XLYC2002082)+1 种基金National Key Research and Development Plan Key Special Projects of Science and Technology Military Civil Integration(Grant No.2022YFF1400500)the Key Project of Science and Technology Commission of the Central Military Commission.
摘要This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapidly-exploring Random Trees*(Q-RRT*)algorithm.A cost inequality relationship between an ancestor and its descendants was derived,and the ancestors were filtered accordingly.Secondly,the underwater gravity-aided navigation path planning system was designed based on the DSFS algorithm,taking into account the fitness,safety,and asymptotic optimality of the routes,according to the gravity suitability distribution of the navigation space.Finally,experimental comparisons of the computing performance of the ChooseParent procedure,the Rewire procedure,and the combination of the two procedures for Q-RRT*and DSFS were conducted under the same planning environment and parameter conditions,respectively.The results showed that the computational efficiency of the DSFS algorithm was improved by about 1.2 times compared with the Q-RRT*algorithm while ensuring correct computational results.
摘要This study explores the application of parallel algorithms to enhance large-scale sorting, focusing on the QuickSort method. Implemented in both sequential and parallel forms, the paper provides a detailed comparison of their performance. This study investigates the efficacy of both techniques through the lens of array generation and pivot selection to manage datasets of varying sizes. This study meticulously documents the performance metrics, recording 16,499.2 milliseconds for the serial implementation and 16,339 milliseconds for the parallel implementation when sorting an array by using C++ chrono library. These results suggest that while the performance gains of the parallel approach over its serial counterpart are not immediately pronounced for smaller datasets, the benefits are expected to be more substantial as the dataset size increases.
摘要模块化多电平换流器(modular multi-level converter,简称MMC)的子模块均压有利于降低开关损耗,消除直流侧环流,被广泛应用于高压直流(high-voltage direct current,简称HVDC)输电系统中.基于快速选择排序算法,对MMC进行分组排序研究,在快速选择排序基础上设计改进快速选择排序,以时间复杂度为目标进行优化.基于子模块电容电压上限和直流电压波动范围提出双电压限原则,并对子模块进行分组,以降低开关损耗.通过在SIMULINK上进行仿真试验,论证改进快速排序算法和分组双电压限排序的可行性.结果显示:改进快速选择算法比传统排序算法速度提高将近8倍;基于双电压限的分组方法可以有效降低开关频率.