Abstract: Multi-User Multiple Input, Multiple Output (MU-MIMO) data transmissions are provided with a forward-predictive precoding matrix to mitigate the effects of a change in a state of a communication channel. First and second soundings are performed, at first and second times, to a receive antenna over a channel and, responsive to each of the soundings, first and second Channel State Information (CSI) are received. Based on the first and second CSI, a change in a state of the channel over a time period between the first and second time is determined. Based on the change in the state of the channel, a forward-predictive channel state matrix and/or a forward-predictive precoding matrix are determined that reflect a state of the channel at a future time and that are consistent with the determined change in the state over the time period. The forward-predictive precoding matrix is applied to a data transmission.

Abstract: An engineering system for collecting and utilizing regional rainwater includes a rainwater collection system, a water quality treatment system, and a control and allocation system. The rainwater collection system includes a rainwater collection ditch for a hardened underlying surface, a barrier and a water storage tank. The water quality treatment system includes a filter system. The control and allocation system includes a water quality monitoring device, a water level monitor, a control gate and a water pump. The filter system is connected to the underlying surface through the rainwater collection ditch, and the filter system is connected to the water storage tank. The control gate is disposed between the filter system and the water storage tank. The water quality monitoring device and the water level monitor are disposed within the water storage tank. The water pump is used to drain water from the water storage tank.

Abstract: A method of forming a porous three-dimensional (3D) is disclosed. The method comprises (I) printing a first composition on a substrate (16) with the nozzle (12) of the apparatus (10) to form at least one first filament (14) comprising the first composition, (II) selectively controlling the distance and/or the speed such that the at least one first filament coils on the substrate to give a first layer on the substrate, the first layer comprising a coiled filament, optionally repeating steps I) and II) with independently selected composition(s) for any additional layer(s), and (III) exposing the layer(s) to a solidification condition. A porous three-dimensional (3D) article formed in accordance with the method is also disclosed.

Abstract: According to a machining principle of the CNC gear hobbing machine, a functional relation between a geometric error of a gear and a tracking error of each motion axis of the machine tool is constructed; a machining error mathematical model of tooth profile deviation, tooth pitch deviation and tooth direction deviation at each position control time point is established by tracking errors of each motion axis; a compensation quantity required for a workpiece rotation axis at the next position control time point is calculated by establishing a decoupling compensation model; average absolute values of machining errors and a total compensation quantity of the machining errors under the conditions of not adopting the synchronous control method and adopting the synchronous control method in the total position control time are obtained by calculating machining error values of each position controls time point, and the synchronized multi-axis motion control is completed.

Abstract: According to a machining principle of the CNC gear hobbing machine, a functional relation between a geometric error of a gear and a tracking error of each motion axis of the machine tool is constructed; a machining error mathematical model of tooth profile deviation, tooth pitch deviation and tooth direction deviation at each position control time point is established by tracking errors of each motion axis; a compensation quantity required for a workpiece rotation axis at the next position control time point is calculated by establishing a decoupling compensation model; average absolute values of machining errors and a total compensation quantity of the machining errors under the conditions of not adopting the synchronous control method and adopting the synchronous control method in the total position control time are obtained by calculating machining error values of each position controls time point, and the synchronized multi-axis motion control is completed.

Abstract: An engineering system for collecting and utilizing regional rainwater includes a rainwater collection system, a water quality treatment system, and a control and allocation system. The rainwater collection system includes a rainwater collection ditch for a hardened underlying surface, a barrier and a water storage tank. The water quality treatment system includes a filter system. The control and allocation system includes a water quality monitoring device, a water level monitor, a control gate and a water pump. The filter system is connected to the underlying surface through the rainwater collection ditch, and the filter system is connected to the water storage tank. The control gate is disposed between the filter system and the water storage tank. The water quality monitoring device and the water level monitor are disposed within the water storage tank. The water pump is used to drain water from the water storage tank.

Abstract: A method of forming a porous three-dimensional (3D) is disclosed. The method comprises (I) printing a first composition on a substrate (16) with the nozzle (12) of the apparatus (10) to form at least one first filament (14) comprising the first composition, (II) selectively controlling the distance and/or the speed such that the at least one first filament coils on the substrate to give a first layer on the substrate, the first layer comprising a coiled filament, optionally repeating steps I) and II) with independently selected composition(s) for any additional layer(s), and (III) exposing the layer(s) to a solidification condition. A porous three-dimensional (3D) article formed in accordance with the method is also disclosed.