Joint Transceiver Designs for Full-Duplex MIMO SWIPT Systems Based on MSE Criterion

For the simultaneous wireless information and power transfer(SWIPT), the full-duplex MIMO system can achieve simultaneous transmission of information and energy more efficiently than the half-duplex. Based on the mean-square-error(MSE) criterion, the optimization problem of joint transceiver design with transmitting power constraint and energy harvesting constraint is formulated. Next, by semidefinite relaxation(SDR) and randomization method, the SDRbased scheme is proposed. In order to reduce the complexity, the closed-form scheme is presented with some simplified measures. Robust beamforming is then studied considering the practical condition. The simulation results such as MSE versus signal-noise-ratio(SNR), MSE versus the iteration number, well prove the performance of the proposed schemes for the system model.

Experimental Investigation of Folding Damage for the Rigidizable Carbon-Epoxy Composites

This paper focused on the folding damage behavior of the space rigidizable materials in terms of 3-1ayer composite membranes. An experimental scheme was presented. The composite membranes were folded between the two plates for a short time, and then the unfolded composite membranes were compressively cured in an oven. By adjusting the displacement of one plate, the folding radius was changed. As expected, the strength and effective modulus of the cured composite membranes drop with decreasing the folding radius. When the strain controlled failure rule is appliedto the composite membranes, a minimal folding radius can be reached, beyond which the membranes will keep intact.Furthermore, folding damage due to folding and unfolding processes was evaluated by a simplified model. Compared with the measured residual strength and effective modulus, calculated results have the same trend. A discrepancy is attributed to neglecting the effects of the transverse fibers and the matrix.

“Liquid diode”with“gating”based on shape memory sponge

Superwetting Janus membranes with unique ability in unidirectional liquid transportation,known as“liquid diode”,have attracted much attention.Recently,endowing the Janus membranes with smart controllability becomes a new research hotspot.However,related reports are still rare and limited in regulating surface wettability,which can hardly avoid some imperfections such as the necessary constant external stimuli and change of water solution.Herein,we advanced an unprecedented strategy to smartly control the liquid permeation on Janus membrane by regulating the pore structure of the material,and report a smart Janus sponge(SJS)that is constructed from a super-hydrophilic sponge(SHS)and a hydrophobic shape memory sponge(HSMS).The pore size and thickness of the HSMS can be reversibly changed as it is pressed/recovered based on the excellent shape memory effect.With the variation of the HSMS,the water permeation performance can be smartly controlled,which is embodied in that only when the HSMS is in the pressed state,SJS acts as a“liquid diode”,otherwise it can prevent liquid from penetrating on either side.Finally,based on the smart controllability of the SJS,we simulated the scene of drug administration and demonstrated its potential application in the field of wound dressing.This work firstly reports a shape memory Janus membrane and provides a new way to control the liquid permeation,which can successfully avoid those shortcomings existing in current wetting-responsive Janus membranes.Given its excellent controllability,we believe it has potential applications in intelligent manipulation of liquid.