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This article investigates the power allocation problem between multiple statistical multiple-input multiple-output(MIMO) radar networks and multiple jammers. Specifically, the main objective of multiple statistical MIMO radar networks is to maximize the mutual information(MI) between the received signal and the path gain matrix under power constraints, whereas the jammers aim to minimize the MI. Based on the theory of Stackelberg game, multiple statistical MIMO radar networks and the jammers are taken as the leader, respectively, and the power allocation problem between the opposing players is effectively solved by using the Lagrange multiplier method. In addition, we derive the existence and uniqueness of the Stackelberg equilibria. Finally, we provide simulation results and compare the performance with other algorithms.

This article investigates the strategy design problem between a multiple statistical MIMO radar network and a jammer, whose primary objective is to minimize their transmission power while satisfying a certain standard. Their conflict relationship is depicted as a two-person zero-sum (TPZS) game due to their adversarial nature. Mutual information (MI) is employed as the utility function where the multiple statistical MIMO radar network and the jammer can change their power allocation strategy to satisfy MI standards for the two players separately. The Stackelberg game is used to study and generate the equilibrium solutions for the strategy design between the multiple statistical MIMO radar network and the jammer. Finally, the simulation results show that, compared with other algorithms, the proposed method can save the leader’s total power under a certain MI standard and has less algorithm complexity.

Implementing an interactive mixed reality simulation system is an economical and risk‐free method for skill training. However, research to enhance the accuracy of mixed reality simulation has always been a challenge. One of the key indicators of a simulation's accuracy is the user's depth perception. Adding depth cues to the simulation scene can effectively increase the accuracy of depth perception. Therefore, in this study, we designed five depth cues to find the one most beneficial for depth perception: (1) depth bar, (2) location ball, (3) fixed window, (4) 3D wireframe, and (5) movable silhouettes. These depth cues were tested using an experimental system with two sets of experimental settings. The first experiment compared the five depth cues at five different viewing distances and showed that the movable silhouettes benefited depth perception accuracy the most. The second experiment compared depth perception accuracies among three different horizontal tilt settings, showing that depth perception accuracy is dependent on the horizontal tilt. Furthermore, different depth perception accuracies were obtained with and without depth cues, proving that the effects from the horizontal tilts were independent of depth cues. The results of these studies provide references for designing interactive mixed reality simulation systems.

In this work, a new nanoarchitectonics of ZnO/Mn3O4/Co3O4(ZnMnCoO) was prepared by solvothermal and calcining processes, and used to degrade tetracycline (TC) with peroxymonosulfate (PMS) as oxidant. Coupling of trace Co3O4(1.48 wt% Co) and difference in work functions of ZnO, Mn3O4, Co3O4enabled ZnMnCoO to possess good PMS activation performance. 97.8% of TC was degraded in 30 min with reactive rate constant of 0.166 min–1, which was 2.6 and 1.4 times higher than those of Mn3O4/PMS and ZnO/Mn3O4/PMS systems, respectively. It was found that SO4•–, O2•−, 1O2, and complex-mediated electron transfer played the main roles in oxidizing TC. In addition, ZnMnCoO was attached to a polytetrafluoroethylene microfiltration membrane to degrade TC via a flow-through device, and 92.4% of TC (10 ppm TC, tap water) and 78.2% of total organic carbon were removed in 120 min. This study designs a novel composite with low Co content to efficiently activate PMS and degrade antibiotics.

Nature provides various exquisite photonic structures of antireflection. Here, we investigate the color and structure of the inner surface of the shell edge (ISSE) of blue mussel shells, using a fiber optical spectrometer, scanning electron microscope (SEM), and X-ray diffraction (XRD). We demonstrate that the structurally assisted black color of the ISSE is produced by a pyramidal microstructure. Furthermore, we use the two-step biotemplate (TSBT) method to successfully replicate this microstructure. Particularly, we modify this method by using a poly(vinyl alcohol) (PVA) film as the negative replica and an epoxy resin film as the positive replica both fabricated without vacuum treatment. We show that the natural and replicated structures show a reflectivity of ∼4% and of ∼3% in the visible wavelength. Finally, we hope our investigation can provide basic data for the study of the bioinspired antireflective structures, which have a promising application in smart windows and optical devices.

A N-doped carbon-wrapped Co9S8catalyst (N-C/Co9S8) was prepared in this work by pyrolysis sulfurized-ZIF-67 and melamine mixture. The prepared catalyst was used to degrade tetracycline (TC) with peroxymonosulfate (PMS) as oxidant. The optimized catalyst could remove 96.8% TC in 15min with a rate constant of 0.196min–1. The degradation mechanism, intermediates, and possible pathway were discussed. It was found that pyridinic N, Co-N, Co species, S2–, C-S-C, and C-SOxwere active sites to activate PMS. The N-doped carbon (N-C) could facilitate electron transfer. The surface-bound ·OH, SO4•−, and ⋅O2−radicals, especially 1O2and electron transfer mechanism contributed to TC degradation. The effects of solution pH, inorganic ions and humic acid on TC degradation were discussed. This study might prompt the development of other ZIF-67-derived sulfides for environmental remediation.

KTa0.65Nb0.35O3(KTN) thin films were prepared by sol-gel process on Pt(111)/Ti/MgO(100) substrates from KOAc, Ta(OC2H5)5and Nb(OC2H5)5in ethanol. The KTN thin films had a prefferred (100) orientation on Pt(111)/Ti/MgO(100) substrates and contained a small amount of pyrochlore structure phase. The 0.8-μm-thick KTN film showed a room-temperature relative permittivity of 2160 and a room-temperature dielectric loss of 0.0098 at 1.0 kHz. The maximum relative permittivity of the KTN film was 4232 at 294 K and 1.0 kHz. The remanent polarization and coercive field of the KTN film were 2.8 μC/cm2and 5.0 kV/cm, respectively, at 263 K.