针对工业装配任务,尤其是不规则轴孔工件装配中,基于学习的前期样本质量低、训练过程不稳定等问题,提出一种融合引斥力模型(Attraction-Repulsion Model,ARM)引导机制和长短期记忆网络(Long Short Term Memory,LSTM)的柔性演员-评论家(S...针对工业装配任务,尤其是不规则轴孔工件装配中,基于学习的前期样本质量低、训练过程不稳定等问题,提出一种融合引斥力模型(Attraction-Repulsion Model,ARM)引导机制和长短期记忆网络(Long Short Term Memory,LSTM)的柔性演员-评论家(Soft Actor-Critic,SAC)算法。首先,为解决训练初期探索效率低的问题,提出一种基于引斥力模型的策略引导机制,通过目标位置信息引导机械臂运动,加速收敛过程;其次,基于长短期记忆网络对算法的策略网络和价值网络进行改进,有效利用历史信息,增强策略学习能力,提高算法的收敛速度和稳定性。仿真结果表明,所提出的算法在行星减速器中心轴装配任务中取得显著的效果,装配成功率高达99.4%,与普通SAC算法相比,平均最大接触力和力矩分别降低了68.8%和79.2%。在物理环境中装配成功率达95%以上,最大接触力和力矩分别小于10 N和1.5 N·m,验证了算法的有效性。展开更多
为提高现有三维建模方法的精度和效率,研究提出基于无人机倾斜摄影与改进样本一致性迭代算法(Sample Consensus with Iterative Algorithm,SAC-IA)算法的三维建模方法,通过结合无人机多视角高分辨率影像采集技术,和改进SAC-IA与迭代最...为提高现有三维建模方法的精度和效率,研究提出基于无人机倾斜摄影与改进样本一致性迭代算法(Sample Consensus with Iterative Algorithm,SAC-IA)算法的三维建模方法,通过结合无人机多视角高分辨率影像采集技术,和改进SAC-IA与迭代最近点算法协同优化点云配准过程,有效提升建筑物三维建模的精度与速度。研究方法在XX古建筑的数字修复实验中成功应用,准确恢复了建筑物的细节,包括屋顶雕花和外立面的裂缝修复,相比传统的地面激光扫描和摄影测量技术,点云配准误差减少了17%~39%。且建模效率较传统方法提高了45%。由此证明,研究方法在提高建筑三维建模精度的同时,也提升了数据采集和处理效率,为复杂建筑物和大规模场景的三维建模提供可靠且高效的解决方案。展开更多
Background Broiler chickens are most vulnerable immediately after hatching due to their immature immune systems,making them susceptible to infectious diseases.The yolk plays an important role in early immune defence b...Background Broiler chickens are most vulnerable immediately after hatching due to their immature immune systems,making them susceptible to infectious diseases.The yolk plays an important role in early immune defence by showing relevant antioxidant and passive immunity capabilities during broiler embryonic development.The immunomodulatory effects of phytogenic compound carvacrol have been widely reported.After in ovo delivery in the amniotic fluid during embryonic development carvacrol is known to migrate to the yolk sac.However,it is unknown whether carvacrol in the yolk could enhance defence responsiveness in the yolk sac.Therefore,the aim of this study was to improve early immune function in chicken embryos,and it was hypothesized that in ovo delivery of carvacrol would result in immunomodulatory effects in the yolk sac,potentially improving post-hatch resilience.Methods On embryonic day(E)17.5,either a saline(control)or carvacrol solution was injected into the amniotic fluid.Yolk sac tissue samples were collected at E19.5,and transcriptomic analyses using RNA sequencing were performed,following functional enrichment analyses comparing the control(saline)and carvacrol-injected groups.Results The results showed that 268 genes were upregulated and 174 downregulated in the carvacrol group compared to the control(P<0.05;logFC<-0.5 or log FC>0.5).Functional analyses of these differentially expressed genes,using KEGG,REACTOME,and Gene Ontology databases,showed enrichment of several immune-related pathways.This included the pathways‘Antimicrobial peptides’(P=0.001)and‘Chemoattractant activity’(P=0.004),amongst others.Moreover,the‘NOD-like receptor signaling’pathway was enriched(P=0.002).Antimicrobial peptides are part of the innate immune defence and are amongst the molecules produced after the nucleotide oligomeriza-tion domain(NOD)-like receptor pathway activation.While these responses may be associated with an inflammatory reaction to an exogenous threat,they could also indicate that in ovo delivery of carvacrol could prepare the newly hatched chick against bacterial pathogens by potentially promoting antimicrobial peptide production through acti-vation of NOD-like receptor signaling in the yolk sac.Conclusion In conclusion,these findings suggest that in ovo delivery of carvacrol has the potential to enhance anti-pathogenic and pro-inflammatory responses in the yolk sac via upregulation of antimicrobial peptides,and NOD-like receptor pathways.展开更多
文摘针对工业装配任务,尤其是不规则轴孔工件装配中,基于学习的前期样本质量低、训练过程不稳定等问题,提出一种融合引斥力模型(Attraction-Repulsion Model,ARM)引导机制和长短期记忆网络(Long Short Term Memory,LSTM)的柔性演员-评论家(Soft Actor-Critic,SAC)算法。首先,为解决训练初期探索效率低的问题,提出一种基于引斥力模型的策略引导机制,通过目标位置信息引导机械臂运动,加速收敛过程;其次,基于长短期记忆网络对算法的策略网络和价值网络进行改进,有效利用历史信息,增强策略学习能力,提高算法的收敛速度和稳定性。仿真结果表明,所提出的算法在行星减速器中心轴装配任务中取得显著的效果,装配成功率高达99.4%,与普通SAC算法相比,平均最大接触力和力矩分别降低了68.8%和79.2%。在物理环境中装配成功率达95%以上,最大接触力和力矩分别小于10 N和1.5 N·m,验证了算法的有效性。
文摘为提高现有三维建模方法的精度和效率,研究提出基于无人机倾斜摄影与改进样本一致性迭代算法(Sample Consensus with Iterative Algorithm,SAC-IA)算法的三维建模方法,通过结合无人机多视角高分辨率影像采集技术,和改进SAC-IA与迭代最近点算法协同优化点云配准过程,有效提升建筑物三维建模的精度与速度。研究方法在XX古建筑的数字修复实验中成功应用,准确恢复了建筑物的细节,包括屋顶雕花和外立面的裂缝修复,相比传统的地面激光扫描和摄影测量技术,点云配准误差减少了17%~39%。且建模效率较传统方法提高了45%。由此证明,研究方法在提高建筑三维建模精度的同时,也提升了数据采集和处理效率,为复杂建筑物和大规模场景的三维建模提供可靠且高效的解决方案。
基金support by AgriFutures Australia’s Chicken Meat Program[grant number PRJ-011584]is gratefully acknowledged.
文摘Background Broiler chickens are most vulnerable immediately after hatching due to their immature immune systems,making them susceptible to infectious diseases.The yolk plays an important role in early immune defence by showing relevant antioxidant and passive immunity capabilities during broiler embryonic development.The immunomodulatory effects of phytogenic compound carvacrol have been widely reported.After in ovo delivery in the amniotic fluid during embryonic development carvacrol is known to migrate to the yolk sac.However,it is unknown whether carvacrol in the yolk could enhance defence responsiveness in the yolk sac.Therefore,the aim of this study was to improve early immune function in chicken embryos,and it was hypothesized that in ovo delivery of carvacrol would result in immunomodulatory effects in the yolk sac,potentially improving post-hatch resilience.Methods On embryonic day(E)17.5,either a saline(control)or carvacrol solution was injected into the amniotic fluid.Yolk sac tissue samples were collected at E19.5,and transcriptomic analyses using RNA sequencing were performed,following functional enrichment analyses comparing the control(saline)and carvacrol-injected groups.Results The results showed that 268 genes were upregulated and 174 downregulated in the carvacrol group compared to the control(P<0.05;logFC<-0.5 or log FC>0.5).Functional analyses of these differentially expressed genes,using KEGG,REACTOME,and Gene Ontology databases,showed enrichment of several immune-related pathways.This included the pathways‘Antimicrobial peptides’(P=0.001)and‘Chemoattractant activity’(P=0.004),amongst others.Moreover,the‘NOD-like receptor signaling’pathway was enriched(P=0.002).Antimicrobial peptides are part of the innate immune defence and are amongst the molecules produced after the nucleotide oligomeriza-tion domain(NOD)-like receptor pathway activation.While these responses may be associated with an inflammatory reaction to an exogenous threat,they could also indicate that in ovo delivery of carvacrol could prepare the newly hatched chick against bacterial pathogens by potentially promoting antimicrobial peptide production through acti-vation of NOD-like receptor signaling in the yolk sac.Conclusion In conclusion,these findings suggest that in ovo delivery of carvacrol has the potential to enhance anti-pathogenic and pro-inflammatory responses in the yolk sac via upregulation of antimicrobial peptides,and NOD-like receptor pathways.
