Astrocytes, the dominant glial cell type, modulate synaptic information transmission. Each astrocyte is organized in non-overlapping domains. Here, a formally based model of the possible significance of astrocyte doma...Astrocytes, the dominant glial cell type, modulate synaptic information transmission. Each astrocyte is organized in non-overlapping domains. Here, a formally based model of the possible significance of astrocyte domain organization is proposed. It is hypothesized that each astrocyte contacting n neurons with m synapses via its processes generates dynamic domains of synaptic interactions based on qualitative criteria so that it exerts a structuring of neuronal information processing. The formalism (morpho-grammatics) describes the combinatorics of the various astrocytic receptor types for occupancy with cognate neurotransmitters. Astrocytic processes are able both to contact synapses and retract from them. Rhythmic oscillations of the astrocyte may program the domain organization, where clock genes may play a role in rhythm generation. For the interpretation of a domain organization a player of a string instrument is used as a paradigm. Since astrocytes form networks (syncytia), the interactions between astrocyte domains may be comparable to the improvisations in a jazz ensemble. Given the fact of a high combinational complexity of an astrocyte domain organization, which is formally demonstrable, and an uncomputable complexity of a network of astrocyte domains, the model proposed may not be testable in biological brains, but robotics could be a real alternative.展开更多
随着计算机视觉技术的不断迭代和发展,以计算机视觉技术为核心的智能应用和设备逐渐在人们的日常生活和工作中扮演越来越重要的角色。其中,基于视觉的同步定位与建图技术(Simultaneous Localization and Mapping,SLAM)在机器人、无人机...随着计算机视觉技术的不断迭代和发展,以计算机视觉技术为核心的智能应用和设备逐渐在人们的日常生活和工作中扮演越来越重要的角色。其中,基于视觉的同步定位与建图技术(Simultaneous Localization and Mapping,SLAM)在机器人、无人机、自动驾驶等领域中被广泛应用,上述领域需要视觉SLAM技术为其提供精准的定位信息,以实现其精确建图和自主导航功能。然而,由于视觉SLAM算法本身的特性,计算量极大,数据依赖性极高,导致其在传统的硬件平台(CPU或GPU)上运行时,难以满足前述边缘端应用场景对实时性和低功耗的需求,成为限制视觉SLAM技术被广泛应用的关键因素。为了解决这一问题,本文基于算法与硬件协同设计的优化策略,针对ORB特征提取和匹配算法提出了一种面向视觉SLAM的高能效专用加速器,通过多种硬件设计技术提高计算性能和能效,包括基于数据依赖关系解耦的多层次并行计算技术、基于多尺寸存储桶的数据存储技术和像素级对称-轻量化描述子生成和方向计算策略。提出的视觉SLAM加速器在Xilinx ZCU104上进行了测试和验证。与ORB SLAM2的算法精度对比,本加速器的精度在5%以内,帧率提升至108 fps,与同期其他硬件加速器相比,查找表使用降低了32.7%,FF使用降低了41.17%,同时帧率提升了1.4倍和0.74倍。展开更多
文摘Astrocytes, the dominant glial cell type, modulate synaptic information transmission. Each astrocyte is organized in non-overlapping domains. Here, a formally based model of the possible significance of astrocyte domain organization is proposed. It is hypothesized that each astrocyte contacting n neurons with m synapses via its processes generates dynamic domains of synaptic interactions based on qualitative criteria so that it exerts a structuring of neuronal information processing. The formalism (morpho-grammatics) describes the combinatorics of the various astrocytic receptor types for occupancy with cognate neurotransmitters. Astrocytic processes are able both to contact synapses and retract from them. Rhythmic oscillations of the astrocyte may program the domain organization, where clock genes may play a role in rhythm generation. For the interpretation of a domain organization a player of a string instrument is used as a paradigm. Since astrocytes form networks (syncytia), the interactions between astrocyte domains may be comparable to the improvisations in a jazz ensemble. Given the fact of a high combinational complexity of an astrocyte domain organization, which is formally demonstrable, and an uncomputable complexity of a network of astrocyte domains, the model proposed may not be testable in biological brains, but robotics could be a real alternative.
