Federated Learning for Microwave Filter Behavior Prediction

Deep learning (DL) technologies have been widely investigated to improve the performance of microwave device behavior prediction. Advanced microwave-related DL technologies utilize independent computers to collect data from the electronic design automation (EDA) software. However, it is essential to note that DL requires a vast amount of high-quality training data. Collecting these data from exact simulation meticulous optimization in EDA is exceptionally time-consuming and computationally intensive. A straightforward way to speed up the process is by collecting quality data from distributed radio frequency (RF) designers. However, this approach may not always be feasible due to the need to maintain the confidentiality of sensitive microwave design information. In this letter, we proposed a federated learning (FL) framework for corporately training DL models for microwave filter behavior prediction. The FL framework aggregates knowledge from various designers without sharing their raw data. The primary experimental results demonstrate the feasibility of the proposed encrypted FL framework for microwave filter applications with superior accuracy and speed

Enhancing strength and electrical conductivity of pure aluminum by microalloying with telluride

The effects of Te addition on the microstructure, strength and electrical conductivity of pure aluminum were investigated, for improving the strength and electrical conductivity of resulting alloys. It was found that the tensile strength and electrical conductivity of the studied alloys increased by 25.8% and 2.8%, respectively, compared with those for pure aluminum (58 MPa and 62.06% IACS), respectively, by adding 0.1 wt% Te. Several mechanisms may account for the observed improvement of the alloys’ strength and electrical conductivity. First, Te addition can refine the grain size of pure aluminum by introducing more nucleation sites and suppressing grain growth through boundary precipitation. Second, the precipitation morphology changes from fine-needle or sheet-like to ellipsoidal shapes, likely improving the alloys’ tensile properties. Finally, Te can purify the melts by forming Al-Te-Fe-Si intermetallics at the grain boundaries, likely reducing the lattice distortion and increasing the electrical conductivity

Observation Of Parity-Time Symmetry In Optically Induced Atomic Lattices

We experimentally demonstrate PT-symmetric optical lattices with periodical gain and loss profiles in a coherently prepared four-level N-type atomic system. By appropriately tuning the pertinent atomic parameters, the onset of PT-symmetry breaking is observed through measuring an abrupt phase-shift jump between adjacent gain and loss waveguides. The experimental realization of such a readily reconfigurable and effectively controllable PT-symmetric waveguide array structure sets a new stage for further exploiting and better understanding the peculiar physical properties of these non-Hermitian systems in atomic settings

Response of macrofaunal assemblages to different pollution pressures of two types of ports

Pollution status and benthic ecological quality of the two types of ports were assessed based on heavy metals and macrofaunal assemblages. Macrofaunal abundance and biomass in the industrial port were significantly higher than those in the fishing port. The dominant species of the two ports were Echinocardium cordatum and Nephtys oligobranchia. The AZTI marine biotic index (AMBI), multivariate AMBI, and Shannon-Wiener diversity index demonstrated that the benthic ecological quality of the two ports was moderate to good. The benthic ecological quality of the distant port sites was better than those of the nearby port sites. The geoaccumulation index and the Hakanson potential ecological risk index indicated that mercury posed a serious threat to port sediment pollution. AMBI, multivariate AMBI, and Shannon-Wiener diversity index were not good indicators for heavy metal pollution. The dominant species and Pielou’s evenness index were significantly correlated with heavy metal pollution and were good biological indicators

Parametric excitation of a SiN membrane via piezoelectricity

We develop a stoichiometric silicon nitride (SiN) membrane-based electromechanical system, in which the spring constant of the mechanical resonator can be dynamically controlled via piezoelectric actuation. The degenerate parametric amplifier is studied in this configuration. We observe the splitting of mechanical mode in the response spectra of a phase-sensitive parametric amplifier. In addition, we demonstrate that the quality factor Q of the membrane oscillator can be significantly enhanced by more than two orders of magnitude due to the coherent amplification, reaching an effective Q factor of ∼3 × 108 at room temperature. The nonlinear effect on the parametric amplification is also investigated, as well as the thermomechanical noise squeezing. This system offers the possibility to integrate electrical, optical and mechanical degrees of freedom without compromising the exceptional material properties of SiN membranes, and can be a useful platform for studying cavity optoelectromechanics

Effects of digestible carbohydrate levels on growth performance, feed utilization, body composition, and biochemical indices of juvenile spotted knifejaw, Oplegnathus punctatus

The effects of digestible carbohydrate levels (0–25 %) on growth, body composition, feed efficiency, and biochemical parameters of juvenile Oplegnathus punctatus (IBW, 12.51 ± 0.02 g) were studied. By adjusting the ratio of corn starch to cellulose, six iso-nitrogenous and iso-lipid diets were formulated. Each diet was divided into three groups (18 fish per replication) for 8 weeks. The results showed that specific growth rate (SGR) and weight gain (WG) were significantly improved (P < 0.05) as digestible carbohydrate levels increased from 0 % to 20 %, but this trend was reversed when the level exceeded 20 %. Correspondingly, feed conversion rate (FCR), protein efficiency ratio (PER), and nitrogen retention (NR) values tended to improved. As digestible carbohydrate levels increased from 0 % to 25 %, daily energy intake (DEI) increased while energy retention (ER) decreased (P < 0.05). Additionally, whole-body crude protein and crude lipid content tended to increase with rising digestible carbohydrate levels. The glycogen content in the liver and muscle increased as digestible carbohydrate levels rose from 0 % to 15 %, while plasma triacylglycerol (TG) concentration decreased as digestible carbohydrate levels increased from 0 % to 20 % (P < 0.05). Compared with other groups, fish fed the C25 diet displayed lower (P < 0.05) amylase activity. Based on the quadratic regression analysis of SGR and WG, dietary digestible carbohydrate levels of 18.31–19.00 % can provide maximum growth for juvenile O. punctatus

Tridentate Sulfoxide‑<i>N</i>‑olefin Hybrid Ligands in Rhodium-Catalyzed Asymmetric Allylic Substitution

A well-defined tridentate chiral sulfoxide-N-olefin ligand has been designed and applied in rhodium-catalyzed asymmetric allylic substitutions of racemic allylic carbonates, providing the branched allylic products in good yields with good to high enantioselectivities and excellent regioselectivities. This reaction mechanism, which involves the possible hemilability of olefin coordination on sulfoxide-N-olefin hybrid ligands with rhodium, is elaborated as well