The biological olfactory system is the sensory system responsible for the detection of the chemical composition of the environment. Several attempts to mimic biological olfactory systems have led to various artificial olfactory systems using different technical approaches. Here we provide a parallel description of biological olfactory systems and their technical counterparts. We start with a presentation of the input to the systems, the stimuli, and treat the interface between the external world and the environment where receptor neurons or artificial chemosensors reside. We then delineate the functions of receptor neurons and chemosensors as well as their overall I-O relationships. Up to this point, our account of the systems goes along similar lines. The next processing steps differ considerably: while in biology the processing step following the receptor neurons is the "integration" and "processing" of receptor neuron outputs in the olfactory bulb, this step has various realizations in electronic noses. For a long period of time, the signal processing stages beyond the olfactory bulb, i.e., the higher olfactory centers were little studied. Only recently there has been a marked growth of studies tackling the information processing in these centers. In electronic noses, a third stage of processing has virtually never been considered. In this review, we provide an up-to-date overview of the current knowledge of both fields and, for the first time, attempt to tie them together. We hope it will be a breeding ground for better information, communication, and data exchange between very related but so far little connected fields.

中文翻译：

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脊椎动物气味编码原理和人工化学感应系统

生物嗅觉系统是负责检测环境化学成分的感觉系统。模仿生物嗅觉系统的几次尝试导致了使用不同技术方法的各种人工嗅觉系统。在这里，我们提供了生物嗅觉系统及其技术对应物的平行描述。我们首先介绍系统的输入、刺激，并处理外部世界与受体神经元或人工化学传感器所在的环境之间的界面。然后我们描述了受体神经元和化学传感器的功能以及它们的整体 IO 关系。到目前为止，我们对系统的描述也遵循类似的思路。接下来的处理步骤有很大不同：虽然在生物学中，受体神经元之后的处理步骤是嗅球中受体神经元输出的“整合”和“处理”，但该步骤在电子鼻中有各种实现。长期以来，对嗅球以外的信号处理阶段，即高级嗅觉中枢的研究很少。直到最近，在这些中心处理信息处理的研究才显着增长。在电子鼻中，几乎从未考虑过处理的第三阶段。在这篇评论中，我们提供了两个领域当前知识的最新概述，并首次尝试将它们联系在一起。我们希望它成为更好的信息、通信、