Zigbee is a suite of protocols. Some protocols may have more problems with the propagation delay of such a network, while other protocols might work OK.
I suspect that the CSMA-CA protocol (if you are really using that on each hop) seems likely to perform poorly. This is analogous to the maximum size of an Ethernet network, which is limited by propagation delay.
The ack mechanism probably works poorly, because of the long delay between a packet transmission and the reception of the ack.
The limitation of having only one outstanding (unacknowledged) frame at a time is a problem with a network this large.
The company says it anticipates high-definition video for home security and other uses will be the next mature technology integrated into the IoT domain, hence the introduction of its MatrixCam devkit.
Siemens and Georgia Institute of Technology are partnering to address limitations in the current additive manufacturing design-to-production chain in an applied research project as part of the federally backed America Makes program.
Most of the new 3D printers and 3D printing technologies in this crop are breaking some boundaries, whether it's build volume-per-dollar ratios, multimaterials printing techniques, or new materials types.
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