Recursive hierarchical parametric identification of Wiener-Hammerstein systems based on initial value optimization.

In this paper, a novel recursive hierarchical parametric identification method based on initial value optimization is proposed for Wiener-Hammerstein systems subject to stochastic measurement noise. By transforming the traditional Wiener-Hammerstein system model into a generalized form, the system model parameters are uniquely expressed for estimation. To avoid cross-coupling between estimating block-oriented model parameters, a hierarchical identification algorithm is presented by dividing the parameter vector into two subvectors containing the coupled and uncoupled terms for estimation, respectively.

Triboelectric sensor gloves for real-time behavior identification and takeover time adjustment in conditionally automated vehicles.

The takeover issue, especially the setting of the takeover time budget, is a critical factor restricting the implementation and development of conditionally automated vehicles. The general fixed takeover time budget has certain limitations, as it does not take into account the driver's non-driving behaviors. Here, we propose an intelligent takeover assistance system consisting of all-round sensing gloves, a non-driving behavior identification module, and a takeover time budget determination module.

Involvement of aSPOC in the online updating of reach-to-grasp to mechanical perturbations of hand transport.

Humans adjust their movement to changing environments effortlessly via multisensory integration of the effector's state, motor commands, and sensory feedback. It is postulated that frontoparietal (FP) networks are involved in the control of prehension, with dorsomedial (DM) and dorsolateral (DL) regions processing the reach and the grasp, respectively. This study tested (5F, 5M participants) the differential involvement of FP nodes (ventral premotor cortex - PMv, dorsal premotor cortex - PMd, anterior intraparietal sulcus - aIPS, and anterior superior parietal-occipital cortex - aSPOC) in online adjustments of reach-to-grasp coordination to mechanical perturbations that disrupted arm transport.

High-Viability Circulating Tumor Cells Sorting From Whole Blood at Single Cell Level Using Laser-Induced Forward Transfer-Assisted Microfiltration.

The efficient isolation and molecular analysis of circulating tumor cells (CTCs) from whole blood at single-cell level are crucial for understanding tumor metastasis and developing personalized treatments. The viability of isolated cells is the key prerequisite for the downstream molecular analysis, especially for RNA sequencing. This study develops a laser-induced forward transfer -assisted microfiltration system (LIFT-AMFS) for high-viability CTC enrichment and retrieval from whole blood.

Bimetallic Sulfides CrVS with Loosely Packed Structure: Exploring the Boundary of Conversion and Intercalation Sodium-Ion Storage Mechanism.

Metal sulfide electrodes for sodium-ion batteries face trade-offs among high capacity, fast kinetics, and stability. The challenge lies in breaking and restoring metal-sulfur bonds and allowing rapid ionic transport. Here we explore the boundary of conversion- and intercalation-type metal sulfides to develop ideal sodium-ion storage materials.

Interphase investigation of modified McLachlan model and the 3D finite element method for electrical conductivity.

This paper explores the electrical conductivity interphase of Ag/Epoxy composite using modified McLachlan theory and 3D finite element composite model through experimental verification. The model characteristic presents conductivity as a dynamic function influenced by particle content, particle electrical properties, electrical properties transition, and an exponent. This model was meticulously crafted, considering the intricate interplay between the polymer matrix and silver particles, the tunnelling distance between adjacent silver particles, and the interphase regions around particles.

Developing tough, fatigue-resistant and conductive hydrogels growth of metal dendrites.

Developing hydrogels with high conductivity and toughness a facile strategy is important yet challenging. Herein, we proposed a new strategy to develop conductive hydrogels by growing metal dendrites. Water-soluble Sn ions were soaked into the gel and then converted to Sn dendrites an electrochemical reaction; the excessive Sn ions were finally removed by water dialysis, accompanied by dramatic shrinkage of the gel.

Enlargement of the Surface Area of High-Entropy Alloys with Acid Treatment as Positive Electrode for High Specific Capacitance Supercapacitors.

High-entropy alloys (HEAs), containing five or more elements in equal proportions, have recently made significant achievements in materials science due to their remarkable properties, including high toughness, excellent catalytic, thermal, and electrical conductivity, and resistance to wear and corrosion. This study focuses on a HEA composed of 23Fe-21Cr-18Ni-20Ti-18Mn, synthesized via ball milling. The alloy was treated with hydrochloric acid (HCl) to enhance its active surface area.

Atomic force microscopy combined with microfluidics for label-free sorting and automated nanomechanics of circulating tumor cells in liquid biopsy.

Liquid biopsies are expected to advance cancer management, and particularly physical cues are gaining attention for indicating tumorigenesis and metastasis. Atomic force microscopy (AFM) has become a standard and important tool for detecting the mechanical properties of single living cells, but studies of developing AFM-based methods to efficiently measure the mechanical properties of circulating tumor cells (CTCs) in liquid biopsy for clinical utility are still scarce. Herein, we present a proof-of-concept study based on the complementary combination of AFM and microfluidics, which allows label-free sorting of individual CTCs and subsequent automated AFM measurements of the mechanical properties of CTCs.

Simulation analysis of surgical neck fractures of the humerus related to bone degeneration.

The most common type of proximal humerus fracture is surgical neck fracture. The purpose of this paper is to study the mechanical mechanism and the effect of bone degeneration on humeral surgical neck fractures. The right humerus finite element models were established based on CT computed tomography.

Lignin-containing nanofiber-reinforced flexible strain sensors with excellent mechanical properties and ionic conductivity for human motion detection.

A multifunctional hydrogel with outstanding mechanical properties and excellent ionic conductivity holds immense potential for applications in various fields, such as healthcare monitoring, and various devices, such as wearable devices and flexible electronics. However, developing hydrogels that combine high mechanical strength with efficient electrical conductivity remains a considerable challenge. Herein, an ion-conductive hydrogel with excellent mechanical properties and ionic conductivity is successfully created.

Quasi-vertically asymmetric channels of graphene oxide membrane for ultrafast ion sieving.

The high performance of two-dimensional (2D) channel membranes is generally achieved by preparing ultrathin or forming short channels with less tortuous transport through self-assembly of small flakes, demonstrating potential for highly efficient water desalination and purification, gas and ion separation, and organic solvent waste treatment. Here, we report the construction of vertical channels in graphene oxide (GO) membrane based on a substrate template with asymmetric pores. The membranes achieved water permeance of 2647 L m h bar while still maintaining an ultrahigh rejection rate of 99.

Real-time prediction of heparin concentration in blood extracorporeal circulation by relaxation time distribution (RTD).

Heparin concentration c in a blood extracorporeal circulation has been real-timely predicted based on the relaxation strength Δε at relaxation frequency f extracted by relaxation time distribution (RTD). The simulated extracorporeal circulation was conducted to optimize the number of Δε for the prediction of c using the porcine whole blood (WB) and low-leukocyte and -platelet blood (LLPB) under the condition of the gradual increment of c from 0 to 8 U/mL with constant flow rate and blood temperature. The experimental results show that among the three relaxation strengths Δε, Δε and Δε (in ascending order of frequency), Δε at f = 5.

Bridging Experimentation and Computation: OMSP for Advanced Acrylate Characterization and Digital Photoresin Design in Vat Photopolymerization.

Vat photopolymerization (VPP) is an additive manufacturing method that requires the design of photocurable resins to act as feedstock and binder for the printing of parts, both monolithic and composite. The design of a suitable photoresin is costly and time-consuming. The development of one formulation requires the consumption of kilograms of costly materials, weeks of printing and performance testing, as well as the need to have developers with the expertise and knowledge of the materials used, making the development process cost thousands.

Critical Role of Rubber Functionalities on the Mechanical and Electrical Responses of Carbon Nanotube-Based Electroactive Rubber Composites.

Carbon nanomaterials, particularly carbon nanotubes (CNTs), are widely used as reinforcing fillers in rubber composites for advanced mechanical and electrical applications. However, the influence of rubber functionality and its interactions with CNTs remains underexplored. This study investigates electroactive elastomeric composites fabricated with CNTs in two common diene rubbers: natural rubber (NR) and acrylonitrile-butadiene rubber (NBR), each with distinct functionalities.

Sensorless Junction Temperature Estimation of Onboard SiC MOSFETs Using Dual-Gate-Bias-Triggered Third-Quadrant Characteristics.

Silicon carbide (SiC) metal oxide semiconductor field-effect transistors (MOSFETs) are a future trend in traction inverters in electric vehicles (EVs), and their thermal safety is crucial. Temperature-sensitive electrical parameters' (TSEPs) indirect detection normally requires additional circuits, which can interfere with the system and increase costs, thereby limiting applications. Therefore, there is still a lack of cost-effective and sensorless thermal monitoring techniques.

Geometry-Based Synchrosqueezing S-Transform with Shifted Instantaneous Frequency Estimator Applied to Gearbox Fault Diagnosis.

This paper introduces a novel geometry-based synchrosqueezing S-transform (GSSST) for advanced gearbox fault diagnosis, designed to enhance diagnostic precision in both planetary and parallel gearboxes. Traditional time-frequency analysis (TFA) methods, such as the Synchrosqueezing S-transform (SSST), often face challenges in accurately representing fault-related features when significant mode closely spaced components are present. The proposed GSSST method overcomes these limitations by implementing an intuitive geometric reassignment framework, which reassigns time-frequency (TF) coefficients to maximize energy concentration, thereby allowing fault components to be distinctly isolated even under challenging conditions.

Influence of Initial Gap, Voltage, and Additives on Zinc Microcolumn Morphology by Local Electrochemical Deposition.

Local electrochemical deposition (LECD) is an innovative additive manufacturing technology capable of achieving precise deposition of metallic microstructures. This study delves into the ramifications of pivotal operational parameters-namely, the initial electrode gap, deposition voltage, and additive concentration-on the morphology of zinc microcolumns fabricated through LECD. A holistic approach integrating experimental methodologies with finite element simulations was adopted to scrutinize the influence of these variables on the microcolumns' dimensions, surface morphology, and structural integrity.

Research on Lateral Stability Control of Four-Wheel Independent Drive Electric Vehicle Based on State Estimation.

This paper proposes a hierarchical framework-based solution to address the challenges of vehicle state estimation and lateral stability control in four-wheel independent drive electric vehicles. First, based on a three-degrees-of-freedom four-wheel vehicle model combined with the Magic Formula Tire model (MF-T), a hierarchical estimation method is designed. The upper layer employs the Kalman Filter (KF) and Extended Kalman Filter (EKF) to estimate the vertical load of the wheels, while the lower layer utilizes EKF in conjunction with the upper-layer results to further estimate the lateral forces, longitudinal velocity, and lateral velocity, achieving accurate vehicle state estimation.

Squat Motion of a Humanoid Robot Using Three-Particle Model Predictive Control and Whole-Body Control.

Squatting is a fundamental and crucial movement, often employed as a basic test during robot commissioning, and it plays a significant role in some service industries and in cases when robots perform high-dynamic movements like jumping. Therefore, achieving continuous and precise squatting actions is of great importance for the future development of humanoid robots. In this paper, we apply three-particle model predictive control (TP-MPC) combined with weight-based whole-body control (WBC) to a humanoid robot.

Graphene-Based, Flexible, Wearable Piezoresistive Sensors with High Sensitivity for Tiny Pressure Detection.

Flexible, wearable, piezoresistive sensors have significant potential for applications in wearable electronics and electronic skin fields due to their simple structure and durability. Highly sensitive, flexible, piezoresistive sensors with the ability to monitor laryngeal articulatory vibration supply a new, more comfortable and versatile way to aid communication for people with speech disorders. Here, we present a piezoresistive sensor with a novel microstructure that combines insulating and conductive properties.

Studies on the High-Power Piezoelectric Property Measurement Methods and Decoupling the Power and Temperature Effects on PZT-5H.

For those piezoelectric materials that operate under high-power conditions, the piezoelectric and dielectric properties obtained under small signal conditions cannot be directly applied to high-power transducers. There are three mainstream high-power characterization methods: the constant voltage method, the constant current method, and the transient method. In this study, we developed and verified a combined impedance method that integrated the advantages of the constant voltage and current methods, along with an improved transient method, for high-power testing of PZT-5H piezoelectric ceramics.

The Influence of Rice Husk Ash Incorporation on the Properties of Cement-Based Materials.

Rice husk ash is a kind of biomass material. Its main component is silicon dioxide, with a content of up to 80%. It has high pozzolanic activity and can react with hydroxide in cement.

FSW Optimization: Prediction Using Polynomial Regression and Optimization with Hill-Climbing Method.

This study presents the optimization of the friction stir welding (FSW) process using polynomial regression to predict the maximum tensile load (MTL) of welded joints. The experimental design included varying spindle speeds from 600 to 2200 rpm and welding speeds from 100 to 350 mm/min over 28 experimental points. The resulting MTL values ranged from 1912 to 15,336 N.

Topology Design of Soft Phononic Crystals for Tunable Band Gaps: A Deep Learning Approach.

The phononic crystals composed of soft materials have received extensive attention owing to the extraordinary behavior when undergoing large deformations, making it possible to provide tunable band gaps actively. However, the inverse designs of them mainly rely on the gradient-driven or gradient-free optimization schemes, which require sensitivity analysis or cause time-consuming, lacking intelligence and flexibility. To this end, a deep learning-based framework composed of a conditional variational autoencoder and multilayer perceptron is proposed to discover the mapping relation from the band gaps to the topology layout applied with prestress.