Acoustic-Field Beamforming-Based Generalized Coherence Factor for Handheld Ultrasound

Handheld ultrasound devices have been widely used for diagnostic applications. The use of the acoustic-field beamforming (AFB) method has been proposed for handheld ultrasound to reduce electricity consumption and avoid battery and unwanted heat issues. However, the image quality, such as the contrast ratio and contrast-to-noise-ratio, are poorer with this technique than with the conventional delay-and-sum method. To address the problems associated with the worse image quality in AFB imaging, in this paper we propose the use of an AFB-based generalized coherence factor (GCF) technique, in which the GCF weighting developed for adaptive beamforming is extended to AFB. Simulation data, experimental results, and in vivo testing verified the efficacy of our proposed AFB-based GCF technique.

Universal synthesis of conductive liquid network in polymers enabling elastic printed circuit board technology

Stretchable electronics are considered next-generation electronic devices in a broad range of emerging fields, including soft robotics1,2, biomedical devices3,4, human-machine interfaces5,6, and virtual or augmented reality devices7,8. A stretchable printed circuit board (S-PCB) is a basic conductive framework for the facile assembly of system-level stretchable electronics with various electronic components. Since an S-PCB is responsible for electrical communications between numerous electronic components, the conductive lines in S-PCB should strictly satisfy the following features: (i) metallic conductivity, (ii) constant electrical resistance during dynamic stretching, and (iii) tough interface bonding with various components9. Despite recent significant advances in intrinsically stretchable conductors10,11,12, they cannot simultaneously satisfy the above stringent requirements. Here, we present a new concept of conductive liquid network-based elastic conductors. These conductors are based on unprecedented liquid metal particles assembled network (LMPNet) and an elastomer. The unique assembled network structure and reconfigurable nature of the LMPNet conductor enabled high conductivity, high stretchability, tough adhesion, and imperceptible resistance changes under large strains, which enabled the first elastic-PCB (E-PCB) technology. We synthesized LMPNet through an acoustic field-driven cavitation event in the solid state. When an acoustic field is applied, liquid metal nanoparticles (LMPnano) are remarkably generated from original LMPs and assemble into a highly conductive particle network (LMPNet). Finally, we demonstrated a multi-layered E-PCB, in which various electronic components were integrated with tough adhesion to form a highly stretchable health monitoring system. Since our synthesis of LMPNet is universal, we could synthesize LMPNet in various polymers, including hydrogel, self-healing elastomer and photoresist and add new functions to LMPNet.

Experimental classical entanglement in a 16 acoustic qubit-analogue

The possibility of achieving and controlling scalable classically entangled, i.e., inseparable, multipartite states, would fundamentally challenge the advantages of quantum systems in harnessing the power of complexity in information science. Here, we investigate experimentally the extent of classical entanglement in a $$16$$ 16 acoustic qubit-analogue platform. The acoustic qubit-analogue, a.k.a., logical phi-bit, results from the spectral partitioning of the nonlinear acoustic field of externally driven coupled waveguides. Each logical phi-bit is a two-level subsystem characterized by two independently measurable phases. The phi-bits are co-located within the same physical space enabling distance independent interactions. We chose a vector state representation of the $$16$$ 16 -phi-bit system which lies in a $${2}^{16}$$ 2 16 -dimensional Hilbert space. The calculation of the entropy of entanglement demonstrates the possibility of achieving inseparability of the vector state and of navigating the corresponding Hilbert space. This work suggests a new direction in harnessing the complexity of classical inseparability in information science.

Methodology of the selection of effective dipping and control over the filling depth of open-textured construction materials

It is determined that for the combination of the dipping process with the ultrasound control it is necessary to carry out the optimization of the filling speed and the precision of control over the dipping depth, to determine the optimum frequency of the ultrasound emission which satisfies the speed and the dipping measurement precision of the sample with the hydrophobic agent. On the basis of the performed multiobjective optimization, experimental results for the dipping and the control over the dipping stage of porous materials by the solution in the uniform acoustic field alignment charts are received for the selection of the rational frequency of ultrasound fluctuations which allow regulating and/or optimizing dipping and control processes over the material filling depth subject to customer tasks. The selection methodology of effective values of parameters of the acoustic field providing the combination of filling processes and the control over the depth of the dipped material filling is well-reasoned.

Measurement and Characterisation of a Diffuse Acoustic Field Using a Phased Array

A diffuse acoustic field has been increasingly used to infer temporal changes in the structures, such as early dislocations and microcracking. This study explores three different techniques to characterise acoustic field by using a single ultrasonic phased array. The first two techniques are proposed to measure spatial uniformity of wave field by examining differences in the integral of energy and the maximum energy respectively at multiple inspection locations. The third one is developed to evaluate the degree of phase coherence between propagating waves transmitted sequentially by two neighbouring array elements. The efficacy of these techniques are investigated by examining their metrics on simulations and well-known samples. The results suggest that two selected metrics can be used to quantitatively estimate the diffuse field start time as well as the field size by comparing their value with the idealised diffuse state (15% for the energy integral metric, ηarea and 1 for the phase coherence metric, ηphase) and identifying the convergence start point.