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
In order to improve the charging efficiency of lead acid battery, shorten the charging time and avoid the battery polarization, a new charging method was put forward. Based on the analyzed results of charging charact...In order to improve the charging efficiency of lead acid battery, shorten the charging time and avoid the battery polarization, a new charging method was put forward. Based on the analyzed results of charging characteristic of lead acid battery, a pulse quick charger is designed to adjust the charging current pulse’s amplitude and pulse width automatically stage by stage according to the measured battery voltage and feedback current. Compared with other kinds of quick chargers, it has such characteristics as shorter charging time, higher charging efficiency and lower temperature increasing during the charging process. As a result, the battery polarization is reduced efficiently.展开更多
德国亚琛工业大学(RWTH-Aachen)作为AMS-01和AMS-02的参与者计划在AMS实验无法继续的基础上,利用高空探测气球进行暗物质的探测。该项目就是为了研究暗物质而开展的试验,论文介绍Positron Electron Balloon Spectrometer(PEBS)的数据采...德国亚琛工业大学(RWTH-Aachen)作为AMS-01和AMS-02的参与者计划在AMS实验无法继续的基础上,利用高空探测气球进行暗物质的探测。该项目就是为了研究暗物质而开展的试验,论文介绍Positron Electron Balloon Spectrometer(PEBS)的数据采集部分,前端探测器部分可以查阅AMS的相关网页。展开更多
The interior forest of protected area（PA）recover quickly in terms of greater diversity and structural complexity than peripheral and outsides, which may be due to high plant-frugivore interactions in the interior fo...The interior forest of protected area（PA）recover quickly in terms of greater diversity and structural complexity than peripheral and outsides, which may be due to high plant-frugivore interactions in the interior forest than the disturbed outsides. To describe the structural and functional differences in tree communities from interior to outside forests with in small PA, we quantitatively analyzed the vegetation of Trishna Wildlife Sanctuary, a rich primate habitat of Northeast India. Vegetation was sampled at C10 cm girth at breast height by 10 m 9 500 m sized20 line transects（10 ha） laid in the interior（N = 7）,peripheral（N = 7） and outside（N = 6） zones of this sanctuary. All transects were ordinated by Principal Component Analysis based on correlation between diversity and existing disturbance indices. We found significant differences（P ／ 0.05） in taxonomic richness and diversity indices between the habitat. Van diagram confirmed greater unique species richness in the interior zone（64） than peripheral（28） and outside（6） zones. Overall density（ha-1） did not differed across the zones, but basal area（m2ha-1） was significantly（P ／ 0.01） high in peripheral zone. Vertical distribution of stem density was linearly declined across zones（r2adj[ 0.70; P ／ 0.01） with increase in the canopy height. Horizontal distribution of adult stems showed significant inverse quadratic relationship（r2adj[ 0.80; P ／ 0.001）, which suggests very low density of canopy forming voluminous trees in the interior zone.Immediate protection, restoration and management of interior regions are required to preserve local plant genetic diversity and also to maintain suitable habitat for threatened wildlife.展开更多
Multi-protocol label switching（MPLS） has the advantage of high efficiency in the second layer, which improves the performance of data packets routing. In this paper, a new structure to implement optical MPLS is prop...Multi-protocol label switching（MPLS） has the advantage of high efficiency in the second layer, which improves the performance of data packets routing. In this paper, a new structure to implement optical MPLS is proposed. We construct a code family for spectral-amplitude coding（SAC） labels in the optical MPLS networks. SAC labels are suitable for optical packet switching because they can be constructed and recognized quickly at each router. We use the label stacking to provide hierarchical routing to avoid swapping labels at each forwarding node and reduce system complexity. However, the phase-induced intensity noise（PIIN） appears due to the incoherent property of the light source when the stacked labels set makes the correlation decoding with the local node label,which degrades system performance.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.
文摘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.
文摘In order to improve the charging efficiency of lead acid battery, shorten the charging time and avoid the battery polarization, a new charging method was put forward. Based on the analyzed results of charging characteristic of lead acid battery, a pulse quick charger is designed to adjust the charging current pulse’s amplitude and pulse width automatically stage by stage according to the measured battery voltage and feedback current. Compared with other kinds of quick chargers, it has such characteristics as shorter charging time, higher charging efficiency and lower temperature increasing during the charging process. As a result, the battery polarization is reduced efficiently.
文摘德国亚琛工业大学(RWTH-Aachen)作为AMS-01和AMS-02的参与者计划在AMS实验无法继续的基础上,利用高空探测气球进行暗物质的探测。该项目就是为了研究暗物质而开展的试验,论文介绍Positron Electron Balloon Spectrometer(PEBS)的数据采集部分,前端探测器部分可以查阅AMS的相关网页。
基金finically supported by the Department of Biotechnology(DBT)Govt.of India,through DBT Network Project(BT/PR7928/NDB/52/9/2006)
文摘The interior forest of protected area（PA）recover quickly in terms of greater diversity and structural complexity than peripheral and outsides, which may be due to high plant-frugivore interactions in the interior forest than the disturbed outsides. To describe the structural and functional differences in tree communities from interior to outside forests with in small PA, we quantitatively analyzed the vegetation of Trishna Wildlife Sanctuary, a rich primate habitat of Northeast India. Vegetation was sampled at C10 cm girth at breast height by 10 m 9 500 m sized20 line transects（10 ha） laid in the interior（N = 7）,peripheral（N = 7） and outside（N = 6） zones of this sanctuary. All transects were ordinated by Principal Component Analysis based on correlation between diversity and existing disturbance indices. We found significant differences（P ／ 0.05） in taxonomic richness and diversity indices between the habitat. Van diagram confirmed greater unique species richness in the interior zone（64） than peripheral（28） and outside（6） zones. Overall density（ha-1） did not differed across the zones, but basal area（m2ha-1） was significantly（P ／ 0.01） high in peripheral zone. Vertical distribution of stem density was linearly declined across zones（r2adj[ 0.70; P ／ 0.01） with increase in the canopy height. Horizontal distribution of adult stems showed significant inverse quadratic relationship（r2adj[ 0.80; P ／ 0.001）, which suggests very low density of canopy forming voluminous trees in the interior zone.Immediate protection, restoration and management of interior regions are required to preserve local plant genetic diversity and also to maintain suitable habitat for threatened wildlife.
文摘Multi-protocol label switching（MPLS） has the advantage of high efficiency in the second layer, which improves the performance of data packets routing. In this paper, a new structure to implement optical MPLS is proposed. We construct a code family for spectral-amplitude coding（SAC） labels in the optical MPLS networks. SAC labels are suitable for optical packet switching because they can be constructed and recognized quickly at each router. We use the label stacking to provide hierarchical routing to avoid swapping labels at each forwarding node and reduce system complexity. However, the phase-induced intensity noise（PIIN） appears due to the incoherent property of the light source when the stacked labels set makes the correlation decoding with the local node label,which degrades system performance.
