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A flexible conducting lossy shield is developed and demonstrated for a reduction in the back radiation of a linearly polarized X-band patch antenna for Wireless Body Area Network (WBAN) applications. The proposed structure comprises a flexible patch antenna backed by a laminated sheet of Expanded Graphite (EG). This flexible sheet is prepared from EG powder pressed uniformly over a thin adhesive tape. The conducting nature of EG is exploited, and the EG sheet is used as a protective shield to prevent back radiation emanating out of the WBAN antenna from propagating toward the human body. The antenna performance is tested over human wrist phantoms experimentally and through full wave simulation studies. The results indicate the marginal variation in the −10 dB impedance bandwidth with a slight increase in the gain and directivity values for a resonant frequency in the range 9.7–10.3 GHz (bending radius variation of 40, 30, and 20 mm and along two bending planes). A measured on-body gain of 6.7 dBi is exhibited by the antenna backed by the EG shield and bent over a 20 mm radius human wrist phantom with an S11 of −19 dB, a −10 dB % bandwidth of 8%, and a directivity of 9.4 dBi. All the other bending configurations exhibit values higher than these. Electric field and Specific Absorption Rate (SAR) studies reveal a reduction in wave penetration by the EG shield antenna inside the wrist phantom with a decrease in the SAR by a maximum of 5%. The measured front-to-back ratio values indicate the lowering of back radiation with a maximum average increase of 76% exhibited by an EG backed antenna. The developed EG shield has an additional advantage of being a standalone structure, which can be integrated with any wearable antenna for a possible reduction in the back radiation. [ABSTRACT FROM AUTHOR]

We present a new library designed to provide a simple and straightforward way to implement QM/AMOEBA (Atomic Multipole Optimized Energetics for Biomolecular Applications) and other polarizable QM/MM (Molecular Mechanics) methods based on induced point dipoles. The library, herein referred to as OpenMMPol, is free and open-sourced and is engineered to address the increasing demand for accurate and efficient QM/MM simulations. OpenMMPol is specifically designed to allow polarizable QM/MM calculations of ground state energies and gradients and excitation properties. Key features of OpenMMPol include a modular architecture facilitating extensibility, parallel computing capabilities for enhanced performance on modern cluster architectures, a user-friendly interface for intuitive implementation, and a simple and flexible structure for providing input data. To show the capabilities offered by the library, we present an interface with PySCF to perform QM/AMOEBA molecular dynamics, geometry optimization, and excited-state calculation based on (time-dependent) density functional theory. [ABSTRACT FROM AUTHOR]

A new non-empirical ab initio intermolecular force field (NICE-FF in buffered 14-7 potential form) has been developed for nucleic acids and beyond based on the dimer interaction energies (IEs) calculated at the spin component scaled-MI-second order Møller–Plesset perturbation theory. A fully automatic framework has been implemented for this purpose, capable of generating well-polished computational grids, performing the necessary ab initio calculations, conducting machine learning (ML) assisted force field (FF) parametrization, and extending existing FF parameters by incorporating new atom types. For the ML-assisted parametrization of NICE-FF, interaction energies of ∼18 000 dimer geometries (with IE < 0) were used, and the best fit gave a mean square deviation of about 0.46 kcal/mol. During this parametrization, atom types apparent in four deoxyribonucleic acid (DNA) bases have been first trained using the generated DNA base datasets. Both uracil and hypoxanthine, which contain the same atom types found in DNA bases, have been considered as test molecules. Three new atom types have been added to the DNA atom types by using IE datasets of both pyrazinamide and 9-methylhypoxanthine. Finally, the last test molecule, theophylline, has been selected, which contains already-fitted atom-type parameters. The performance of NICE-FF has been investigated on the S22 dataset, and it has been found that NICE-FF outperforms the well-known FFs by generating the most consistent IEs with the high-level ab initio ones. Moreover, NICE-FF has been integrated into our in-house developed crystal structure prediction (CSP) tool [called FFCASP (Fast and Flexible CrystAl Structure Predictor)], aiming to find the experimental crystal structures of all considered molecules. CSPs, which were performed up to 4 formula units (Z), resulted in NICE-FF being able to locate almost all the known experimental crystal structures with sufficiently low RMSD20 values to provide good starting points for density functional theory optimizations. [ABSTRACT FROM AUTHOR]

We report a flexible language-model-based deep learning strategy, applied here to solve complex forward and inverse problems in protein modeling, based on an attention neural network that integrates transformer and graph convolutional architectures in a causal multi-headed graph mechanism, to realize a generative pretrained model. The model is applied to predict the secondary structure content (per-residue level and overall content), protein solubility, and sequencing tasks. Further trained on inverse tasks, the model is rendered capable of designing proteins with these properties as target features. The model is formulated as a general framework, completely prompt-based, and can be adapted for a variety of downstream tasks. We find that adding additional tasks yields emergent synergies that the model exploits in improving overall performance, beyond what would be possible by training a model on each dataset alone. Case studies are presented to validate the method, yielding protein designs specifically focused on structural materials, but also exploring the applicability in the design of soluble, antimicrobial biomaterials. While our model is trained to ultimately perform eight distinct tasks, with available datasets, it can be extended to solve additional problems. In a broader sense, this study illustrates a form of multiscale modeling that relates a set of ultimate building blocks (here, byte-level utf8 characters that define the nature of the physical system at hand) to complex output. This materiomic scheme captures complex emergent relationships between universal building block and resulting properties, via a synergizing learning capacity, to express a set of potentialities embedded in the knowledge used in training via the interplay of universality and diversity. Significance statement: Predicting the properties of materials based on a flexible description of their structure, environment, or process, is a long-standing challenge in multiscale modeling. Our MaterioFormer language model, trained to solve forward and inverse tasks, incorporates a deep learning capacity through attention and graph strategies to yield a multimodal approach to model and design materials. Since our model is prompt-based and information is encoded consistently via byte-level utf8 tokenization, it can process diverse modalities of information, such as sequence data, description of tasks, and numbers, and offers a flexible workflow that integrates human intelligence and artificial intelligence. Autoregressive training, using pre-training against a large unlabeled dataset, allows for straightforward adjustment of specific objectives. [ABSTRACT FROM AUTHOR]

A novel laser thermal printing technique toward the fabrication of all‐in‐one flexible intelligent devices is presented in this work, addressing the existing challenges in their scalable manufacturing and multifunctional performance. The first‐ever application of this technique for the synthesis of a multifunctional intelligent cobweb structure is presented. The resultant cobweb integrates a conductive network of multi‐walled carbon nanotubes (MWCNTs) and NdFeB magnetic microparticles within a polydimethylsiloxane (PDMS) matrix, enabling seamless incorporation of sensing, stimulus response, and actuation functionalities. The cobweb exhibits multifunctional sensing characteristics, including a 2.37 strain gauge factor and a 0.312%·mT−1 magnetic field sensitivity, excellent stability exceeding 3500 cycles. Furthermore, the cobweb achieves accurate capture of a beetle on the basis of real‐time sensing of the beetle, verifying its rapid stimulus response characteristics. Meanwhile, the cobweb exhibits an electromagnetic ejection performance with an ejection height of over 33.5 times the size of the projectile, verifying its powerful actuating ability. These results demonstrate the successful integration of multifunctional sensing, stimulus response, and actuation within the cobweb structure, facilitated by the innovative laser thermal printing process. The laser thermal printing technique marks a significant advancement in the efficient fabrication of miniaturized and multifunctional flexible intelligent devices based on thermosetting materials. [ABSTRACT FROM AUTHOR]

An innovative experimental method, called aeroelastic real-time hybrid simulation (aeroRTHS), is proposed to study the aerodynamic vibrations of a building model in a boundary layer wind tunnel (BLWT). The aeroRTHS method aims to capture the dynamic interactions between an aeroelastic structure and the applied wind load to accurately characterize complicated, unstable phenomena such as vortex-induced vibration, and in doing so, to broaden the application of real-time hybrid simulation (RTHS) from seismic applications to wind engineering. The aeroRTHS tests were conducted in the BLWT at the University of Florida Natural Hazards Engineering Research Infrastructure Equipment Facility (UF NHERI EF). A 1-m-tall rigid physical model with an aspect ratio (height/width) of 7.3 was mounted on a modified single-axis shake table converting translational motions to corresponding rotations at the base of the model allowing the model to behave in the wind tunnel as an aeroelastic structure. A total of 128 pressure sensors located on the cross-wind sides of the physical building model measured wind pressures which then were converted to equivalent forces and ultimately resolved into a single equivalent force at the top of the physical building model based on the moment equilibrium at its base. The results from a series of aeroRTHS tests in the BLWT are reported herein to constitute a proof-of-concept study that validates the aeroRTHS method and demonstrates the aeroelastic effects on a flexible and slender structure. [ABSTRACT FROM AUTHOR]

The need for sustainable energy sources is growing significantly on a global scale due to the on-going energy crises and issues with environmental degradation. In order to achieve sustainable growth for the environment and energy, it is essential to increase recuperation during the transmission of energy. Pulsating heat pipes (PHP), a type of two-phase heat transfer device, have been extremely popular for over a decade for a wide range of applications. PHP has attracted much interest because of its unique operating principle and outstanding thermal performance. This review highlights the impact of influencing factors on PHP thermal performance. Based on the outcomes of the researchers' latest numerical and experimental investigations, it is clear that their effects are quite significant since PHP's hydrodynamic as well as thermodynamic effects are interrelated, and it was also found that heat input is a major contributor (almost 40% to 50%) among all influencing factors on PHP performance. Furthermore, this review has also addressed the concept of flexible structure heat pipes, which offer great potential for use in compact, complex, and bendable electronic systems. Moreover, recent developments in PHP applications in emerging sectors, including electric vehicles, solar energy systems, and heat recovery systems are described. [ABSTRACT FROM AUTHOR]

Seismic design tools are based on surrogate models of the designed structure and the responses of those surrogates to earthquake ground motions. To design symmetric flexible rocking structures, a surrogate model that includes rocking and flexure is needed. In this paper, we derive the equation of motion of a flexible multi‐degree‐of‐freedom (MDOF) structure rocking on its base in modal coordinates. Then, we introduce a set of two‐degree‐of‐freedom (2DOF) surrogate models that accounts only for the first elastic vibration mode of the multimass structure and its rotation about the base pivot points. We investigate the surrogates' ability to represent the dynamics of an elastic MDOF structure that uplifts and rocks and the interaction between rocking and flexure. Therein, we detail the simplifications for the equations of motion of the 2DOF surrogate models and the adopted rocking impact model, and develop and check the sliding initiation condition. We show that the simplified 2DOF surrogate model responses compare well to experimental results. Then we assess the 2DOF surrogate model accuracy in representing the earthquake response of the MDOF model using Cloud Analysis and the coefficient of determination R2$R^2$ approach. We find that simplified 2DOF surrogate of the MDOF model is quite accurate (R2=0.99$R^2\,=\,0.99$) in estimating its maximum relative top displacement and acceptably accurate (R2=0.90$R^2\,=\,0.90$) in estimating its maximum base rotation based on a thousand randomly generated flexible rocking structure earthquake response analyses. Lastly, we discuss using the simplified 2DOF surrogate model of symmetric flexible rocking structures in preliminary seismic design, and give examples featuring a continuous elastic hollow semi‐conical chimney and an inelastic flexible MDOF structure, both with a base that may uplift. [ABSTRACT FROM AUTHOR]

The innovation of high‐performance, stable electrocatalysts for clean energy systems faces significant challenges. Metal‐organic frameworks (MOFs), with their porous nature, flexible structures, and homogeneous active site dispersion, have gained interest as unique precursors for carbon‐based catalysts. MOFs' properties significantly enhance catalytic performance in fuel cells. This review highlights recent advancements in MOF design for oxygen electrocatalysis in fuel cells, while also discussing perspectives for future material innovations to improve catalytic activity in this emerging field. [ABSTRACT FROM AUTHOR]

Nitrogen‐containing heterocyclic molecules feature metal resource‐independence, flexible conjugation structure and fast charge storage kinetics, making them promising to be used as the electrode material in lithium‐ion batteries. However, an insufficiently high capacity (<400 mAh g−1) seriously threatens their practical application. Herein, a novel molecule, viz. 3,6‐bis(2‐pyrimidinyl)‐1,2,4,5‐tetrazine (DPmT), is developed by inserting an electron‐withdrawing π‐bridge unit of s‐tetrazine between two pyrimidine rings, in which a dense assembly of multiple active sites is realized. The DTmP exhibits a remarkable atom economy of 40 g (mol e)−1, which refers to the molecule mass per unit of charge transferred. The cathode material of DPmT yields a high capacity of 653 mAh g−1 and an energy density of 1188 Wh kg−1 at 50 mA g−1 at 70 °C. And 80% capacity retention is achieved after 500 cycles at 500 mA g−1, confirming its superior cyclability. Spectroscopy studies and theoretical calculations are performed to investigate the charge storage process. First, the C═N and N═N are claimed as plausible binding sites for the lithium ions. Second, the introduction of s‐tetrazine significantly enhances molecular planarity, thereby promoting charge delocalization and molecular stability. This work provides a novel strategy for designing atom‐economic multi‐charge electrode materials with high capacity. [ABSTRACT FROM AUTHOR]

Material handling is a widely used process in manufacturing and is generally considered a non-value-added process. The Dynamic Facility Layout Problem (DFLP) considered in this paper minimizes the total material handling and re-arrangement cost. In this study, an integrated DFLP model with unequal facility areas, assignment of material handling devices (MHD), and flexible bay structure (FBS) is considered, and it is aimed to propose fast solution approaches. Two different solution methods are proposed for the problem, which are the genetic algorithm and the simulated annealing algorithm, respectively. In both methods, a non-linear mathematical model solution was used to calculate the fitness values. Thus, the solutions in the feasible solution space are utilized. The proposed solution approaches were applied to solve four problems published in the literature. The computational experiments have validated the effectiveness of the algorithms and the quality of solutions produced. [ABSTRACT FROM AUTHOR]

Single atom catalysts (SACs) exhibit the flexible coordination structure of the active site and high utilization of active atoms, making them promising candidates for nitrogen reduction reaction (NRR) under ambient conditions. By the aid of first‐principles calculations based on DFT, we have systematically explored the NRR catalytic behavior of thirteen 4d‐ and 5d‐transition metal atoms anchored on 2D porous graphite carbon nitride C5 ${_5 }$ N2 ${_2 }$. With high selectivity and outstanding activity, Zr, Nb, Mo, Ta, W and Re‐doped C5 ${_5 }$ N2 ${_2 }$ are identified as potential nominees for NRR. Particularly, Mo@C5 ${_5 }$ N2 ${_2 }$ possesses an impressive low limiting potential of −0.39 V (corresponding to a very low temperature and atmospheric pressure), featuring the potential determining step involving *N−N transitions to *N−NH via the distal path. The catalytic performance of TM@C5 ${_5 }$ N2 ${_2 }$ can be well characterized by the adsorption strength of intermediate *N2 ${_2 }$ H. Moreover, there exists a volcanic relationship between the catalytic property UL ${_{\rm{L}} }$ and the structure descriptor Ψ ${{{\Psi }}}$ , which validates the robustness and universality of Ψ ${{{\Psi }}}$ , combined with our previous study. This work sheds light on the design of SACs with eminent NRR performance. [ABSTRACT FROM AUTHOR]

In diverse materials science spanning from fine ceramics to lithium-ion batteries and fuel cells, the particle–binder interactions in slurries play a crucial role in governing the ultimate performance. Despite numerous efforts to date, quantitatively elucidating these hidden interactions has remained a longstanding challenge. Here, we demonstrate a dynamic approach to evaluate adsorptive interactions between ceramic particles and polymeric binders entangled in a slurry utilizing differential centrifugal sedimentation (DCS). Particles settling under a centrifugal force field impart significant viscous resistance on the adsorbed binder, leading to its detachment, influenced by particle size and density. This behaviour directly reflects the particle–binder interactions, and detailed DCS spectrum analysis enables the quantitative assessment of nano-Newton-order adsorption forces. An important finding is the strong correlation of these forces with the mechanical properties of the moulded products. Our results provide insight that forming a flexible network structure with appropriate interactions is essential for desirable formability. [ABSTRACT FROM AUTHOR]

Decades of research has been dedicated to investigating inverted pavement as an alternative to traditional flexible pavement structures. While previous studies have largely focused on the stress dependency of the unbound aggregate base (UAB) layer using numerical simulations, there is limited research on the construction and use of geogrid reinforcement in inverted pavement. This study presents a comprehensive evaluation of full-scale inverted pavements, specifically assessing the impact of geogrid reinforcement on rutting performance. The results indicate that adding geogrid to the UAB layer improves rutting resistance, with optimal results achieved when the geogrid is placed in the upper third of the layer. On the other hand, when the geogrid was positioned in the bottom two-thirds of the layer, it led to inferior rutting performance compared to the inverted pavement where geogrid reinforcement was placed in the upper one-third of the UAB layer. Numerical simulations validate the field test results, demonstrating that higher tensile strains in the upper third location enhance aggregate interlocking and stiffness due to the geogrid's enhanced constraining capacity and reinforcement. Conversely, lower tensile strains in the bottom two-thirds location limit geogrid constraints, leading to increased rutting and surface deformation. • Structural performance of the inverted pavement was investigated using a full-scale accelerated pavement test. • Geogrid-reinforcing effect within the inverted pavement structure was evaluated. • Optimum position of biaxial geogrid within the unbound aggregate base layer in the inverted pavement was studied. • Geogrid-reinforcing mechanism within the unbound aggregate base layer in the inverted pavement was revealed. [ABSTRACT FROM AUTHOR]

The FinRay soft gripper achieves passive enveloping grasping through its functional flexible structure, adapting to the contact configuration of the object to be grasped. However, variations in beam position and thickness lead to different behaviors, making it important to research the relationship between structure and force. Conventional research using FEM simulations has tested various virtual FinRay models but replicating phenomena such as buckling and slipping has been challenging. While hardware-based methods that involve installing sensors on the gripper and the object to analyze their states have been attempted, no studies have focused on the tangential contact force related to slipping. Therefore, we developed a 16-way object contact force measurement device incorporating two-axis force sensors into each of the 16 segmented objects and compared the normal and tangential components of the enveloping grasping force of the FinRay soft gripper under two types of contact friction conditions. In the first experiment, the proposed device was compared with a device containing a six-axis force sensor in one segmented object, confirming that the proposed device has no issues with measurement performance. In the second experiment, comparisons of the proposed device were made under various conditions: two contact friction states, three object contact positions, and two object motion states. The results demonstrated that the proposed device could decompose and analyze the grasping force into its normal and tangential components for each segmented object. Moreover, low friction conditions result in a wide contact area with lower tangential frictional force and a uniform normal pushing force, achieving effective enveloping grasping. [ABSTRACT FROM AUTHOR]

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development. Under high pressure conditions, small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space, incurring annular pressure build-up and/or production of acidic environment, which poses serious challenges to the structure and integrity of the flexible pipes. Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature, annular structure, external temperature. In a long-distance gas flexible pipe, moreover, gas permeation exhibits non-uniform features, and the gas permeated into the annular space flows along the metal gap. To assess the complex gas transport behavior in long-distance gas flexible pipes, a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes, the diffusion of gas in the inner liner, and the gas seepage in the annular space under varying permeable properties of the annulus. In addition, the effect of a variable temperature is accounted. A numerical calculation method is accordingly constructed to solve the coupling mathematical equations. The annular permeability was shown to significantly influence the distribution of annular pressure. As permeability increases, the annular pressure tends to become more uniform, and the annular pressure at the wellhead rises more rapidly. After annular pressure relief followed by shut-in, the pressure increase follows a convex function. By simulating the pressure recovery pattern after pressure relief and comparing it with test results, we deduce that the annular permeability lies between 123 and 512 mD. The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources. [ABSTRACT FROM AUTHOR]

Flexible silicone materials have excellent elastic properties and can maintain excellent structural stability under high-intensity repeated deformation. They are ideal materials for preparing piezoresistive flexible sensors. However, traditional silicone materials exhibit strong insulation properties. The solid block structure is also not conducive to improving sensitivity. Inspired by the irregular hole structure of Taihu Lake stone, this paper prepared a porous silica gel skeleton (rGO/CTAB/SG) based on reduced graphene oxide film coating, which was equipped with flexible interdigital electrodes to achieve electrical signal derivation. The "honeycomb" shaped sensing module prepared in this way achieves an extremely wide elastic deformation range (20-200%). In the pressure feedback layer, the rGO film is evenly coated on the SG surface, which greatly improves the device conductivity and sensing performance (high sensitivities of 89.4 kPa− 1 and 25.4 kPa− 1 are achieved within 0-30.2 kPa and 30.2–42 kPa, ultra-high durability under more than 22,000 load-unload cycles.) Numerical simulation analysis results confirmed that the structure of the flexible substrate SG prepared by this method maintained well when extreme deformation occurred, and no fracture or stress concentration occurred. As an elastic sensor, after being integrated with a microprocessor, it can easily monitor and analyze human body movement in real time. It has huge potential in areas such as daily training and health monitoring of athletes. [ABSTRACT FROM AUTHOR]

Developing efficient O2 electrocatalyst is crucial for lithium-oxygen (Li-O2) batteries (LOBs). Among various catalysts, perovskite oxides have exhibited diverse catalytic activity owing to their low synthetic cost, tunable constitutions, flexible structures and excellent electrochemical stability. In this research, LaNi0.5Fe0.5O3 perovskites (LNFO) were synthesized via a classical sol–gel route combined with succedent calcination treatment. The ORR and OER tests indicate that the catalytic activity of LNFO calcined at 600 (LNFO-1) and 800℃ (LNFO-3) is superior to that of 700 (LNFO-2) and 900℃ (LNFO-4). To determine which sample is more suitable as a catalyst for LOBs, the LOBs with LNFO-1 and LNFO-3 electrodes were assembled. The LNFO-1 cathode shows discharge capacity of 1.7686 mAh under the current density of 100 mA g−1, which is higher than that with LNFO-3 cathode. The initial discharge–charge profiles of LOBs with LNFO-1 and LNFO-3 electrodes under a cutoff capacity of 1 mAh at 100 mA g−1 indicates that a lower overpotential could gained from LNFO-1 electrode. Meanwhile, 233 and 93 cycles can be realized under capacity limit of 0.15 and 0.315 mAh, respectively, at the current density of 100 mA g−1. The results demonstrate a lower overpotential, and longer circularity can be implemented in the LOB with LNFO-1 cathode, which can be put down to the larger specific surface area, and more presence of Ni3+ and Fe4+ in LNFO-1. Therefore, our work confirmed that the mesoporous LNFO-1 is a promising electrocatalyst for LOBs. [ABSTRACT FROM AUTHOR]

The implementation of flexible plate structures in industrial settings presents a multitude of benefits, including enhanced efficiency and greater flexibility in comparison with rigid structures. Notwithstanding these advantages, malleable plate structures are more prone to vibrations on account of their inadequate rigidity to endure significant levels of vibrational events. To address this issue, it is imperative to develop an accurate model and an efficient control system. This study aims to develop a model and active vibration control-based advanced firefly algorithm (AFA) for a flexible horizontal plate structure. Initially, input and output vibration data are collected based on the experimental rig designed with a flexible horizontal plate structure. The obtained data are later used to model the system using the system identification method utilizing a metaheuristic algorithm with linear auto-regressive with an exogenous model structure. This study introduces a novel AFA optimization, known as the variant of the firefly algorithm (FA), for the model identification of the flexible horizontal plate structure. Results indicated that the model of the flexible horizontal plate structure developed using AFA is better compared to FA. The smallest mean square error training is achieved from the best model by AFA at 1.1090 × 10−5 compared to FA. Subsequently, the developed model is implemented in a control scheme for vibration attenuation of the flexible horizontal plate structure. The proposed proportional–integral–derivative (PID) controller tuned by AFA works well to stop unwanted vibrations. It works better than the PID-FA controller and other control algorithms, reducing vibrations by up to 98.9%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel urchin-like (NH 4) 2 V 10 O 25 ·8H 2 O are synthesized by solvothermal method. • The enlarged interlayer spacing speeds up the Zn2+ insertion/extraction. • The interlayer pillaring facilitates rapid and stable zinc ion storage. • NH 4 + provides a flexible framework structure. • The urchin-like morphology maintains the structural stability during (dis)charging. The practical application of zinc ion batteries (ZIBs) can be facilitated by designing cathode materials with unique structures that can overcome the critical problems of slow reaction kinetics and large volume expansion associated with the intercalation reaction of divalent zinc ions. In this study, a novel urchin-like (NH 4) 2 V 10 O 25 ·8H 2 O assembled from nanorods was synthesized by a simple hydrothermal method, noted as U-NVO. The interlayer organic pillar of cetyltrimethylammonium cation (CTAB) has been intercalated between layers to regulate the interlayer microstructure and expand the interlayer spacing to 1.32 nm, which effectively increased the contact between the electrode and electrolyte interface and shortened the diffusion path of electrolyte ions. The interlayer pillars of structural H 2 O and NH 4 + provide a flexible framework structure and enhance the cohesion of the layered structure, which helps to maintain structural stability during the charging and discharging process, resulting in long-term durability. These unique properties result in the U-NVO cathodes demonstrating high specific capacity (401.7 mA h g−1 at 0.1 A g−1), excellent rate capability (99.6 % retention from 0.1 to 5 A g−1 and back to 0.1 A g−1), and long-term cycling performance (∼87.5 % capacity retention after 2600 cycles). These results offer valuable insights into the design of high-performance vanadium oxide cathode materials. [ABSTRACT FROM AUTHOR]

Periodic high utility sequential pattern mining (PHUSPM) has attracted much attention because it can find more practical regular patterns in time series. However, existing PHUSPM algorithms struggle to effectively handle incremental updates and overlook the downward closure property and complexity of the algorithm in large-scale data. To solve this problem, this paper proposed an IncPUS-Miner algorithm, which effectively realized the incremental mining of periodic high-utility sequential patterns (PHUSPs). IncPUS-Miner introduced a novel data structure called pu-tree. Each tree node corresponded to an updated utility list(UUL) to store the auxiliary information of the corresponding sequence. When incremental data was added, this structure allowed flexible updates to project information, thereby enhancing the dynamic adaptability and scalability of the algorithm. In addition, this paper proposed two new upper bounds of sequence utility, PUB and EUB, and two corresponding pruning strategies, which effectively reduced the computational burden. The experimental results show that the IncPUS-Miner algorithm effectively realizes the incremental mining of PHUSPs on real data, and shows superior performance compared with other algorithms. [ABSTRACT FROM AUTHOR]

Continuum robots, possessing great flexibility, can accomplish tasks in complex work scenes, regarded as an important direction in robotics. However, the current continuum robots are not satisfying enough in terms of fabrication and maintenance, and their workspace is limited by structure and other aspects. In this paper, to address the above problems, a modular deployable robot, which adopts an origami structure instead of a flexible hinge, is proposed. A fabrication method is innovated, the Spherical Linkage Parallel Mechanism (SLPM) unit is optimized, and the installation and fabrication process of the robot is simplified through modularization. The forward kinematics and inverse kinematics of the robot and its workspace are analyzed by using the screw theory. The prototype of the robot is constructed, and its folding performance, bending performance, and motion accuracy are tested, and the error analysis and compensation optimization are carried out. After the optimization, the position error of the robot is reduced by about 65%, and the standard deviation is greatly lowered, which effectively improves the motion accuracy and stability of the robot. [ABSTRACT FROM AUTHOR]

In high-speed and heavy-load conditions, ordinary rigid tilting pad journal bearings experience significant contact stress at the pad pivot points, leading to severe pad deformation and increased wear. A flexible structure tilting pad bearing (FSTPB) is presented in this paper, using spring supports to replace the traditional pivot supports and flexible hinge supports. A theoretical calculation model for tilting pad radial journal bearings considering flexible structure deformation is established, and the impact of elastic deformation on the performance of the flexible structure tilting pad bearings is discussed. Based on theoretical research, vibration experiments on flexible tilting pad bearings under different loading conditions were conducted. The influence of various structural parameters on the vibration characteristics of the flexible tilting pad radial bearings was studied. The results indicate that, compared to ordinary tilting pad bearings, flexible structure tilting pad bearings exhibit excellent vibration reduction characteristics at high speeds. Reducing the bearing clearance, lowering the stiffness of the flexible structure, and increasing the offset angle of the flexible structure contribute to enhancing the operational stability of the bearing–rotor system. [ABSTRACT FROM AUTHOR]

Purpose: Ultra‐high field MRI offers unprecedented detail for noninvasive visualization of the human brain. However, brain imaging is challenging at 7T due to the B 1+$$ {}_1^{+} $$ field inhomogeneity, which results in signal intensity drops in temporal lobes and a bright region in the brain center. This study aims to evaluate using a metasurface to improve brain imaging at 7T and simplify the investigative workflow. Methods: Two flexible metasurfaces comprising a periodic structure of copper strips and parallel‐plate capacitive elements printed on an ultra‐thin substrate were optimized for brain imaging and implemented via PCB. We considered two setups: (1) two metasurfaces located near the temporal lobes and (2) one metasurface placed near the occipital lobe. The effect of metasurface placement on the transmit efficiency and specific absorption rate was evaluated via electromagnetic simulation studies with voxelized models. In addition, their impact on signal‐to‐noise ratio (SNR) and diagnostic image quality was assessed in vivo for two male and one female volunteers. Results: Placement of metasurfaces near the regions of interest led to an increase in homogeneity of the transmit field by 5% and 10.5% in the right temporal lobe and occipital lobe for a male subject, respectively. SAR efficiency values changed insignificantly, dropping by less than 8% for all investigated setups. In vivo studies also confirmed the numerically predicted improvement in field distribution and receive sensitivity in the desired ROI. Conclusion: Optimized metasurfaces enable homogenizing transmit field distribution in the brain at 7T. The proposed lightweight and flexible structure can potentially provide MR examination with higher diagnostic value images. [ABSTRACT FROM AUTHOR]

The study investigates the thermal expansion and superconducting properties of a CuAl2‐type (tetragonal) superconductor CoZr2 under high pressures. High‐pressure synchrotron X‐ray diffraction is performed in a pressure range of 2.9 GPa < P < 10.4 GPa, and it is discovered that CoZr2 exhibits volumetric negative thermal expansion (NTE) under high pressures. Although uniaxial positive thermal expansion (PTE) along the a‐axis is observed under ambient pressure, it is suppressed by pressure, whereas a large uniaxial NTE along the c‐axis is maintained under the pressure regime. Because of the combination of the suppressed uniaxial PTE along the a‐axis and uniaxial NTE along the c‐axis, volumetric NTE is achieved under high pressure in CoZr2. The volumetric NTE mechanism is based on the flexible crystal structure caused by the soft Co–Co bond, as observed in the isostructural compound FeZr2, which exhibits a uniaxial NTE along the c‐axis. High‐pressure electrical resistance measurements of CoZr2 are performed and confirm superconductivity at 0.03 GPa < P < 41.9 GPa. Because of the coexistence of the two phenomena, volumetric NTE and superconductivity, in CoZr2 under high pressure, coexistence can be achieved under ambient pressure by tuning the chemical composition after the present observation. [ABSTRACT FROM AUTHOR]

When structures are subjected to dynamic loading, such as that caused by an earthquake or working machinery, the rocking behavior of objects located on parts of the loaded structure plays an important role in addressing the protection and stability of non-structural components. In this work, the free rocking of a rigid block on a flexible beam and rigid base was investigated using numerical simulations. To this end, a numerical code based on the non-smooth contact dynamics method was developed for this particular problem, and numerical simulations are compared to experimental tests when a rigid base is considered. The purpose of the study was to investigate the predictive capabilities and limitations of the numerical model and address the effect of introducing beam flexibility on the rocking response. The investigated flexibilities were such that the beam deflection under the static weight of the block remains within the common limit of 1/250 of the beam span. For a rigid base, qualitatively good correlation with the experiments was obtained, and good convergence in terms of the time-step is displayed. With the increase in beam base flexibility, it was observed that the simulation results tend to become more sensitive to mesh density and time-step size. Furthermore, we identify a limited flexibility with respect to which unreliable predictions of the overall free rocking are obtained, which corresponds to the stiffness resulting in the beam deflection under the block weight of beam-span/2500. For stiffnesses higher than that, no significant effect of beam flexibility in comparison to the rigid base was noticed in terms of tilt angle and rocking duration, which indicates the adequacy of a rigid base approximation for beams with low flexibility. [ABSTRACT FROM AUTHOR]

Hydrogen‐bonded frameworks have garnered significant attention due to their flexible structures with tailored porosity, making them a promising class of porous framework materials. However, the direct synthesis of hydrogen‐bonded frameworks with specific functions is highly challenging due to the unpredictable formation of hydrogen‐bonded frameworks. In response, postsynthetic modification has emerged as a potent strategy to imbue desired functions into hydrogen‐bonded frameworks. Recent advances have demonstrated the effectiveness of postsynthetic modification in hydrogen‐bonded frameworks for studying their mechanical, luminescent, electrochemical, and chiral properties. In this concept, we comprehensively summarize the methodologies and outcomes of postsynthetic modification to hydrogen‐bonded frameworks, providing a highlight of this exciting research area. [ABSTRACT FROM AUTHOR]

Hydrogels are formed of crosslinked polymer chains arranged in three-dimensional (3D) networks. These chains have good water-containing capacity and are soft and malleable. Hydrogels have good biocompatibility due to their significant water content, flexible structure, and numerous holes. These characteristics make them analogous to biological tissues. Despite the publication of 8700 literature related to hydrogel biomedical applications in the past 52 years (1973 ~ 2024), studies on the use of hydrogels in biomedicine are few. To gain a comprehensive understanding of their current development status, research trends, and prospects in the biomedical application field, it is imperative to conduct a thorough retrospective analysis. In this study, we employ bibliometric analysis and CiteSpace software to quantitatively and visually analyze articles published in this field. Firstly, we provide a quantitative analysis of authorship and institutional publications over the past 52 years to elucidate the fundamental development status regarding hydrogel biomedical applications. Secondly, we did visual studies on terms that are high-frequency, explosive, keyword clustering, and so on, to understand the directionality and evolution of the main research hotspots during each period. Notably, our findings emphasize that fabricating hydrogels into wound healing-promoting dressings emerges as a prominent hotspot within the application field. We anticipate that this paper will inspire researchers with novel ideas for advancing hydrogel applications in biomedicine. [ABSTRACT FROM AUTHOR]

Mechanically deformable flexible temperature sensors are being used to fabricate next-generation smart electronics, but improving their high-temperature application range is still a major challenge. In this work, in pursuit of excellent performance, a series of Mn–Ni–O ultrathin flexible thermal thin films with dual-phase structure were successfully prepared by magnetron sputtering using the bias voltage adjustment method. The interactions of grain density, ionic valence and phase structure on the performance of high-temperature NTC are emphasized. By overcoming the significant drawbacks of the flexible thermal films such as poor stability and narrow temperature range under high temperature conditions, excellent thermal performance with a wide temperature range from 200 °C to 600 °C and a resistance drift rate as low as 1.5 % has been achieved. This opens up innovative prospects for the design and application of flexible high-temperature thermal materials. [ABSTRACT FROM AUTHOR]

The unique structure of nacre is composed of 'bricks' and 'mortar,' which gives it excellent damage resistance. In this study, nacre-like bionic ceramic scaffolds were 3D-printed using vat photopolymerization (VPP) technology, filled with polymer, and reinforced with carbon fiber to create high-strength and high-toughness carbon fiber-reinforced bionic composites. This approach leverages additive manufacturing technology to easily overcome the challenges of fabricating complex bionic structures with a simple and flexible production process. It offers a practical method for developing other lightweight, high-strength, and tough bionic materials. The microstructure of the composites was observed using scanning electron microscopy and energy dispersive spectroscopy. Additionally, finite element method and molecular dynamics simulations were performed on the composites. The results indicate that the composite material increased the flexural strength by 293.52 % and the fracture toughness by 109.36 % compared to solid ceramic parts. The primary toughening mechanisms of carbon fiber include crack deflection, fiber "pull-out," and "debonding" within the composite. [Display omitted] • Nacre-like biomimetic composites were fabricated via vat photopolymerization. • Effects of various fillers on flexural properties were investigated. • Atomic-level insights on biomimetic structures were offered by molecular dynamics. • Finite element method reveals filler interaction with the nacre scaffold. [ABSTRACT FROM AUTHOR]

Emerging research suggests that music and rhythm-based interventions offer promising avenues for facilitating functional outcomes for autistic individuals. Evidence suggests that many individuals with ASD have music processing and production abilities similar to those of neurotypical peers. These individual strengths in music processing and production may be used within music therapy with a competence-based treatment approach. We provide an updated perspective of how music and rhythm-based interventions promote sensory and motor regulation, and how rhythm and music may then impact motor, social, and communicative skills. We discuss how music can engage and motivate individuals, and can be used intentionally to promote skill acquisition through both structured and flexible therapeutic applications. Overall, we illustrate the potential of music and rhythm as valuable tools in addressing skill development in individuals on the autism spectrum. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) are crucial for transferring bioactive materials between cells and play vital roles in both health and diseases. Cellular protrusions, including filopodia and microvilli, are generated by the bending of the plasma membrane and are considered to be rigid structures facilitating various cellular functions, such as cell migration, adhesion, and environment sensing. Compelling evidence suggests that these protrusions are dynamic and flexible structures that can serve as sources of a new class of EVs, highlighting the unique role they play in intercellular material transfer. Cytonemes are specialized filopodia protrusions that make direct contact with neighboring cells, mediating the transfer of bioactive materials between cells through their tips. In some cases, these tips fuse with the plasma membrane of neighboring cells, creating tunneling nanotubes that directly connect the cytosols of the adjacent cells. Additionally, virus particles can be released from infected cells through small bud-like of plasma membrane protrusions. These different types of protrusions, which can transfer bioactive materials, share common protein components, including I-BAR domain-containing proteins, actin cytoskeleton, and their regulatory proteins. The dynamic and flexible nature of these protrusions highlights their importance in cellular communication and material transfer within the body, including development, cancer progression, and other diseases. [ABSTRACT FROM AUTHOR]

In the process of the on–board transportation of liquid hydrogen storage and transportation tanks, apart from considering the support strength and adiabatic performance, it is imperative to take into account the vibration characteristics of the carrying platform. The present work introduces a versatile support structure comprising a damping module and a ball contact insulation structure, enabling effective isolation of external vibrations while simultaneously providing support and insulation. The first step involves describing the principle of a flexible support structure and designing the mechanical structure. Subsequently, a damping analysis is conducted based on dynamic theory to establish the relationship between the spring and damping. Finally, the structural parameters of the dual–function strut are determined, followed by simulation of heat transfer performance. The results demonstrate that the dual–function strut exhibits exceptional vibration damping performance by reducing the amplitude of external vibrations greater than 5 Hz to less than 6%. Moreover, owing to the compact linear diameter spring structure of the vibration damping module and its ball contact effect, the thermal resistance of the dual–function strut is significantly enhanced, resulting in a mere heat leakage of only 22 W/m2 in a single rod section. [ABSTRACT FROM AUTHOR]

The wide utilization of lithium-ion batteries (LIBs) prompts extensive research on the anode materials with large capacity and excellent stability. Despite the attractive electrochemical properties of pure Si anodes outperforming other Si-based materials, its unsafety caused by huge volumetric expansion is commonly admitted. Silicon monoxide (SiO) anode is advantageous in mild volume fluctuation, and would be a proper alternative if the low initial columbic efficiency and conductivity can be ameliorated. Herein, a hybrid structure composed of active material SiO particles and carbon nanofibers (SiO/CNFs) is proposed as a solution. CNFs, through electrospun processes, serve as a conductive skeleton for SiO nanoparticles and enable SiO nanoparticles to be uniformly embedded in. As a result, the SiO/CNF electrochemical performance reaches a peak at 20% the mass ratio of SiO, where the retention rate reaches 73.9% after 400 cycles at a current density of 100 mA g−1, and the discharge capacity after stabilization and 100 cycles are 1.47 and 1.84 times higher than that of pure SiO, respectively. A fast lithium-ion transport rate during cycling is also demonstrated as the corresponding diffusion coefficient of the SiO/CNF reaches ~8 × 10−15 cm2 s−1. This SiO/CNF hybrid structure provides a flexible and cost-effective solution for LIBs and sheds light on alternative anode choices for industrial battery assembly. [ABSTRACT FROM AUTHOR]

While peptide macrocycles with rigidified conformations have proven to be useful in the design of chemical probes of protein targets, conformational flexibility and rapid interconversion can be equally vital for biological activity and favorable physicochemical properties. This study introduces the concept of "structural pin", which describes a hydrogen bond that is largely responsible for stabilizing the entire macrocycle backbone conformation. Structural analysis of macrocycles using nuclear magnetic resonance (NMR), molecular modelling and X‐ray diffraction indicates that disruption of the structural pin can drastically influence the conformation of the entire ring, resulting in novel states with increased flexibility. This finding provides a new tool to interrogate dynamic behaviour of macrocycles. Identification of structural pins offers a useful conceptual framework to understand positions that can either be modified to give flexible structures or retained to maintain the rigidity of the scaffold. [ABSTRACT FROM AUTHOR]

Highlights The polypyrrole wrapped‐carbon nanotube composites with the core‐shell design are prepared via two‐step self‐assembly originated from the multi‐interactions of dopant, zeolitic imidazolate framework, carbon nanotube and pyrrole. The core composed of carbon nanotube effectively improves the conductivity of the composite and provides stable double‐layer capacitance. The shell composed of polypyrrole and tightly wrapped on carbon nanotubes effectively prevents the volume expansion of polypyrrole while undergoing the process of doping/de‐doping as well as endows supercapacitors with high pseudocapacitance. The polypyrrole‐coated carbon nanotube displays a remarkable specific capacitance of 510 F g−1 when operating at a current density of 1 A g−1. Surprisingly, the assembled polypyrrole wrapped‐carbon nanotube//activated carbon asymmetric supercapacitor not only possesses a high capacitance preservation of 88.5% after 10,000 charge/discharge cycles at 5 A g−1, but also shows superior flexibility and stable electrochemical behaviors when subjected to various bending angles. Furthermore, the flexible polypyrrole wrapped‐carbon nanotube//activated carbon supercapacitor achieves the superb energy density of 86.3 Wh kg−1 and the power density of 800 W kg−1 when operating at 1 A g−1. These results highlight the significant potential of this new generation of flexible supercapacitor devices. Polypyrrole is wrapped on carbon nanotube to form a core‐shell structure CNTs improve the conductivity and provides double‐layer capacitance The core‐shell design prevents the volume expansion of polypyrrole The assembled asymmetric supercapacitor shows superior flexibility [ABSTRACT FROM AUTHOR]

Hybrid Foil Magnetic Bearings (HFMBs) are a promising bearing technology for high-speed, oil-free turbomachinery that structurally embeds a gas foil bearing (GFB) into the inner diameter of an active magnetic bearing (AMB). The flexible foil structure provides sufficient support stiffness for the rotor, while closed-loop control allows real-time adjustment of the dynamic performance of the bearing. In this paper, the static and dynamic performance of the HFMB is measured experimentally. The effect of the control gain on the static and dynamic performance of the HFMB is highlighted. The proportional gain increases the stiffness but weakens the stability of the system, while the differential gain increases the damping but unexpectedly increases the stiffness. The static and dynamic performance of the HFMB is compared with that of the GFB. At low excitation frequencies, the stability of the GFB is higher than that of the HFMB, while as the excitation frequency is increased, the stability of the HFMB exceeds that of the GFB. [ABSTRACT FROM AUTHOR]

This study first draws inspiration from the dual biomimetic design of plant cell walls and honeycomb structures, drawing on their structural characteristics to design a flexible shell structure that can achieve significant deformation and withstand large loads. Based on the staggered bonding of this flexible shell structure, we propose a new design scheme for a large-load pneumatic soft arm and establish a mathematical model for its flexibility and load capacity. The extension and bending deformation of this new type of soft arm come from the geometric variability of flexible shell structures, which can be controlled through two switches, namely, deflation and inflation, to achieve extension or bending actions. The experimental results show that under a driving pressure within the range of 150 kpa, the maximum elongation of the soft arm reaches 23.17 cm, the maximum bending angle is 94.2 degrees, and the maximum load is 2.83 N. This type of soft arm designed based on dual bionic inspiration can have both a high load capacity and flexibility. The research results provide new ideas and methods for the development of high-load soft arms, which are expected to expand from laboratories to multiple fields. [ABSTRACT FROM AUTHOR]

A stacked dual‐band antenna system based on frequency selective surface (FSS) is proposed in this paper. The system consists of lower band (LB) and higher band (HB) antenna elements with a frequency ratio of 2.5. FSS is introduced between LB and HB elements, which can fully reflect LB wave and transmit HB wave without reflection. LB and HB antenna arrays can be designed independently and combined with only a few screws, allowing for flexible combination of different arrays according to different needs. The stacked scheme can avoid the generation of grating lobes caused by excessive spacing of HB elements. Two different arrays were analyzed, simulated, and measured to validate the excellent features of the proposed scheme, such as easy to combine, stable radiation patterns, and lower mutual interference for LB and HB elements, respectively. The proposed system can be a promising candidate for dual‐band wireless communication with large frequency ratio. [ABSTRACT FROM AUTHOR]

Perovskites materials, due to their peculiar electronic and ionic properties, play a key role in the development of hydrogen-based technologies. Their flexible structure enables an easy tuning of various physical-chemical characteristics, such as ionic and electronic conductivity and redox active sites concentration, fundamental for these applications. Moreover, the same structure can exhibit different properties that can synergically act to improve the performance of the material for a specific application. [ABSTRACT FROM AUTHOR]

Organic electronics have great potential due to their flexible structure, high performance, and their ability to build effective and low-cost photodetectors. We investigated the parameters of the P3HT and PCBM layers for device performance and optimization. SCAPS-1D simulations were employed to optimize the thicknesses of the P3HT and PCBM layers, investigate the effects of shallow doping in the P3HT layer, and assess the influence of the back contact electrode's work function on device performance. Furthermore, this study explored the impact of interface defect layer density on the characteristics of the device. Through systematic analyses, the optimal parameters for enhancing device responsivity were identified. The findings indicate that a P3HT layer thickness of 1200 nm, a PCBM layer thickness of 20 nm, and a back contact electrode with a work function of 4.9 eV achieve the highest responsivity. Notably, at a bias of −0.5 V, the responsivity exceeds 0.4 A/W within the wavelength range of 450 nm to 630 nm. These optimized parameters underscore the significant potential of the developed device as an organic photodetector, particularly for visible light detection. [ABSTRACT FROM AUTHOR]

The engineering of ferroic orders, which involves the evolution of atomic structure and local ferroic configuration in the development of next‐generation electronic devices. Until now, diverse polarization structures and topological domains are obtained in ferroelectric thin films or heterostructures, and the polarization switching and subsequent domain nucleation are found to be more conducive to building energy‐efficient and multifunctional polarization structures. In this work, a continuous and periodic strain in a flexible freestanding BaTiO3 membrane to achieve a zigzag morphology is introduced. The polar head/tail boundaries and vortex/anti‐vortex domains are constructed by a compressive strain as low as ≈0.5%, which is extremely lower than that used in epitaxial rigid ferroelectrics. Overall, this study c efficient polarization structures, which is of both theoretical value and practical significance for the development of next‐generation flexible multifunctional devices. [ABSTRACT FROM AUTHOR]

Many financial time series not only have varying structures at different quantile levels and exhibit the phenomenon of conditional heteroscedasticity at the same time but also arrive in the stream. Quantile double‐autoregression is very useful for time series analysis but faces challenges with model fitting of streaming data sets when estimating other quantiles in subsequent batches. This article proposes a renewable estimation method for quantile double‐autoregression analysis of streaming time series data due to its ability to break with storage barrier and computational barrier. Moreover, the proposed flexible parametric structure of the quantile function enables us to predict any interested quantile value without quantile curve crossing problem or keeping the desirable monotone property of the conditional quantile function. The proposed methods are illustrated using current data and the summary statistics of historical data. Theoretically, the proposed statistic is shown to have the same asymptotic distribution as the standard version computed on an entire data stream with the data batches pooled into one data set, without additional condition. Simulation studies and an empirical example are presented to illustrate the finite sample performance of the proposed methods. [ABSTRACT FROM AUTHOR]

Background: Digital image correlation (DIC) has been widely used for motion tracking and estimation, however, the process is often sensitive to the initial guess, especially under large translations and rotations. Objective: To provide novel and effective solutions for the DIC in measuring large translations and rotations. Methods: A ring-projection-based two-scale approach is proposed. In the integer-pixel scale, a novel ring projection scheme, including amplitude and phase correlations of the rings, is developed to quickly get the integer-pixel initial estimation of the translations and rotation. In the sub-pixel scale, the gradient-based inverse compositional Gauss-Newton (IC-GN) algorithm, which is free from repeat computation of Hessian matrix, is adopted to efficiently get the optimal motion parameters. Results: The numerical example show that the absolute error is no more than 0.05 pixel for measured large translations and no more than 0.05 ∘ for measured large rotations. While test experiments on a rotated blade and a flexible arch demonstrate the effectiveness, accuracy and applicability of the proposed approach in measuring the rotating motion, flexible large deformation and vibrational modal parameters of structures. Conclusions: The ability and effectiveness of the proposed approach for large translations and rotations measurement have been verified. Since large deformations and rotations are frequently encountered in rotating and flexible structures, the proposed approach is believed to constitute a feasible and powerful tool for static and dynamic deformation measurement of these structures. [ABSTRACT FROM AUTHOR]

• A coupling dynamic model of the non-symmetric spatial dumbbell-type system is developed. • A structure-preserving numerical iteration method is proposed to solve the coupling problems concerned. • The effects of the masses of additional particles on orbit-attitude-vibration coupling behaviors of the model are revealed. The structural symmetric breaking of the spatial structure will enhance the coupling dynamic behaviors and bring new challenges for the dynamic analysis on the spatial structure inevitably. The main contribution of this paper is proposing a structure-preserving iteration method to investigate the effects of the dynamic symmetry-breaking factors on the dynamic behaviors of the rigid-flexible coupling systems. Firstly, the spatial flexible damping beam assembled with two particles on both ends is simplified as an asymmetric spatial dumbbell-type model. For this model, the coupling dynamic equations are presented based on the Hamiltonian variational principle. Then, connecting the symplectic precise integration method for the ordinary differential equations mainly controlling the plane motion of the model and the generalized multi-symplectic scheme for the partial differential equation mainly controlling the transverse vibration of the beam, a structure-preserving numerical iteration method is proposed, which provides a new way to analysis the dynamic behaviors of the coupling problems with the symmetric breaking. Finally, the effects of the absolute mass and the mass ratio of the additional particles on the orbit radius, the orbit true anomaly velocity, the attitude angle velocity of the model and the transverse vibration of the flexible beam are reproduced by using the structure-preserving numerical iteration method in the numerical simulations. Particularly, the effects of the additional particles on the attitude stability of the model and the vibration dissipation of the flexible damping beam are investigated, which gives some guidance for the attitude adjustment strategy and the vibration control method for the spatial flexible structure with the structural symmetric breaking. [ABSTRACT FROM AUTHOR]

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Accepted by: Aris Syntetos This paper examines the impact of temporary supply chain disruptions in a general equilibrium model with multiple stages of production for capital goods and a flexible time-to-build structure. Production disruptions at one or more stages result in declines in overall shipments and increases in the ratios of unfilled orders and work-in-process inventories to shipments. The model is calibrated to industries in durable goods manufacturing during the Covid-19 pandemic, and is shown to generate realistic dynamic responses to temporary production disruptions. Consistent with the data, an unanticipated 1-month disruption to upstream production results in a decline in shipments and an increase in the ratio of unfilled orders to shipments lasting more than 6 months. [ABSTRACT FROM AUTHOR]

Mechanical damage to the surface of polyimide during manufacture and utilization may act as critical determinants of the properties and longevity of the material. In order to address this issue, this study prepared thermoplastic polyimide (TPI) films through the copolymerization of isocyanate and acid anhydride, which possesses superior self‐healing ability after being mechanical damaged. Moreover, polyimide films still retain its exceptional tensile strength (>90 MPa) with Young's modulus (E) (>3 GPa), high thermal stability (glass transition temperature (Tg) >220°C), and excellent insulation performance (breakdown strength (Eb) >180 kV/mm) after self‐healing. Introducing cross‐linked structures and flexible groups into the thermoplastic resin matrix appropriately not only imparts self‐healing capabilities to the material but also retains its excellent mechanical properties. The combination of straightforward copolymerization and distinctive self‐healing prowess renders it an appropriate strategy for confronting self‐healing challenges. [ABSTRACT FROM AUTHOR]

Adaptability to unstructured objects and the avoidance of target damage are critical challenges for flexible grippers in fruit-picking robots. Most existing flexible grippers have many problems in terms of control complexity, stability and cost. This paper proposes a flexible finger design method that considers contact behavior. The new approach incorporates topological design of contact targets and introduces contact stress constraints to directly obtain a flexible finger structure with low contact stress and good adaptability. The study explores the effects of design parameters, including virtual spring stiffness, volume fraction, design domain size, and discretization, on the outcomes of the flexible finger topology optimization. Two flexible finger structures were selected for comparative analysis. The experimental results verified the effectiveness of the design method and the maximum contact stress was reduced by about 70%. An adaptive two-finger gripper was developed. This design allows the gripper to achieve damage-free grasping without additional sensors and control systems. The adaptive and contact performances of the grippers with different driving modes were analyzed. Practical grasping tests were also performed, including evaluation of adaptive performance, stability, and maximum grasping weight. The results indicate that gripper 2 with flexible finger 2 excelled in contact stress and adaptive wrapping, making it well-suited for grasping unstructured and fragile objects. This paper provides valuable insights for the design and application of flexible grippers for picking robots, offering a promising solution to enhance adaptability while minimizing target damage. [ABSTRACT FROM AUTHOR]

Enzymes have flexible structures and can modulate the multiple catalytic sites efficiently for synergistic catalysis. Inspired by enzymes, various artificial catalysts have been designed, while controllable synergistic effects in artificial catalysts have never been reported. Here, we report the first example of photo‐regulated synergistic catalyst (PRSC) and the synergistic effects between acidic and basic sites can be regulated by light. PRSCs have acidic sites on pore walls and basic sites on pendant azobenzene groups, and photo‐regulation is achieved through azobenzene isomerization. In the cascade reaction of converting benzaldehyde dimethyl acetal (BA) to benzylidenemalononitrile (BM), the PRSC shows a change of up to 33.6% in BM yield. Mechanism exploration indicates that cis azobenzene makes the catalytic system more stable. The promoted adsorption energy of the reactant malononitrile (MN) on basic sites and the activated C atom of MN that connects to methylene groups are responsible for the tunable synergistic effects of PRSCs. [ABSTRACT FROM AUTHOR]