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We propose a multi-feed Huygens' metasurface (HMS) transmitarray designed for microwave power transmission applications. A near-field distributed optimization mechanism is employed to determine the optimal focal lengths of subarrays. We aim to balance between illumination efficiency and interference from incident waves, leveraging the conjugate field matching method for precise phase compensation. This approach ensures robust radiation performance, notably reducing the focus-to-diameter ratio for large-aperture antenna arrays. Consequently, it mitigates spatial dispersion effects and upholds the operational bandwidth of mega antennas. As a proof of concept, we have designed a single-layer HMS transmitarray measuring 1.14 × 1.14 m2 (22 λ at 5.8 GHz). Through simulation, we have attained a peak gain of 35.47 dB and an aperture efficiency of 57.73%. Our design exhibits outstanding radiation performance, combined with advantages, such as a low profile, cost-effectiveness, and scalability. [ABSTRACT FROM AUTHOR]

By employing a recently proposed Hubbard U density-corrected scheme within density functional theory, we provide design principles towards the design of materials exhibiting a spin crossover-assisted gas release. Small molecular fragments are used as case study to identify two main mechanisms behind the change in binding energy upon spin transitions. The feasibility of the proposed mechanism in porous crystals is assessed by correlating the change in binding energy of CO2, CO, N2, and H2, upon spin crossover, with the adiabatic energy difference associated with the spin state change of the square-planar metal in Hofmann-type clathrates (M = Fe, Mn, Ni). A few promising cases are identified for the adsorption of intermediate ligand field strength molecules such as N2 and H2. The latter stands out as the most original result as the strong interaction in low spin, as expected from a Kubas mechanism, results in a large change in binding energy. This work provides a general perspective towards the engineering of open-metal site frameworks exhibiting local environments designed to have a spin crossover upon adsorption of specific gas molecules. [ABSTRACT FROM AUTHOR]

Recently, a series of reports showing ultrahigh electrostrains (>1%) have appeared in several Pb-free piezoceramics. The ultrahigh electrostrain has been attributed exclusively to the defect dipoles created in these systems. We examine these claims based on another report (G. D. Adhikary and R. Ranjan, "Ultrahigh measured unipolar strain >2% in polycrystalline bulk piezoceramics: Effects of disc dimension," arxiv.org/abs/2208.07134), which demonstrated that the measured electric field driven strain increased dramatically simply by reducing the thickness of the ceramic disks. We prepared some representative Pb-free compositions reported to exhibit ultrahigh strain and performed electrostrain measurements. We found that these compositions do not show ultrahigh electrostrain if the thickness of the disks is above 0.30 mm (the disk diameters were in the range of 10–12 mm diameter). The ultrahigh strain values were obtained when the thickness was below 0.30 mm. We compare the electrostrain obtained from specimens designed to exhibit defect dipoles with those obtained from stoichiometric compositions of Na0.5Bi0.5TiO3 and K0.5Na0.5NbO3-based lead-free systems and could obtain much higher strain levels (4%–5%) in the later specimens in the small thickness regime. Our results do not favor the defect dipole theory as the exclusive factor for causing ultrahigh strain in piezoceramics. A new approach is called for to understand the phenomenon of ultrahigh electrostrain caused by the thickness reduction of piezoceramic disks. [ABSTRACT FROM AUTHOR]

A new structure with negative stiffness and negative Poisson's ratio was designed to exhibit these characteristics during compression, energy absorption, and energy storage. The structure also shows improved impact resistance under extreme conditions due to transverse contraction during impact compression. These characteristics make the structure very suitable for use in spacecraft landing systems. A finite-element model using the improved Auricchio constitutive model was established, and compression tests were conducted on the new structure. The test results are in agreement with the simulation, validating the finite-element model. Comparing the new structure with traditional structures with negative Poisson's ratio, the new structure demonstrated significantly better energy absorption and experienced minimal deformation during the compression-pull process. In addition, the finite-element model was used to analyze the influence of cell structural parameters. Further analysis showed that cell width and wall thickness of a curved beam are critical parameters influencing the structure's overall energy-absorption performance, which should be emphasized in the design of landing energy-absorption devices with the new structure. [ABSTRACT FROM AUTHOR]

This publication concerns the synthesis of a novel class of hybrid thermoset/thermoplastic elastomers, i.e., double cross‐linked polyisobutylene‐based polyurethanes (xPIB‐PUs), together with their processing and some key properties. These materials are designed to exhibit a combination of properties for indwelling medical applications, specifically for heart valve prostheses. The chemical cross‐links are introduced by well‐defined 3‐arm PIB stars fitted with HO‐end groups of molecular weights (MWs) of Mn = 3081 and 9000 g mole−1 and narrow MW dispersities (<1.3). Processibility of xPIB‐PU containing 70 wt% PIB (for biocompatibility and calcification resistance) is achieved by driving the syntheses to high conversions (>97%) close to but still below the gel point and completing the cross‐linking in heated molds. The processibility period (minutes) is controlled by controlling the MW of the cross‐linking agent in the 3081 to 9000 g mole−1 range. Blends of 3‐arm stars and linear bifunctional PIBs can also control the processibility period. The creep resistance of xPIB‐PU is significantly improved (from 13.2% to 5.5%) relative to physically cross‐linked PIB‐PU. xPIB‐PUs exhibit negligible permanent set (1–2%), and high Young's modulus (41 MPa). The stress/strain properties of xPIB‐PUs are also investigated. The data clearly show the contribution of two modes of cross‐linking. [ABSTRACT FROM AUTHOR]

This paper presents a non-uniform curved grid-stiffened shell design method aiming to enhance structural performance using various stiffener patterns, allowing simultaneous optimization of stiffener thickness and stiffener layout. Firstly, the grid-stiffened cell description function is defined using quadratic polynomial functions, comprising the orthogrid, the triangle grid, the rotated triangle grid, and the Kagome grid. Then, the non-uniform stiffener layout description function is established using the sawtooth function, while a filter function is employed to ensure the smooth and continuous of the stiffeners. Moreover, the analytical sensitivity is thoroughly derived, and the optimization problem is formulated. Finally, the effectiveness of the proposed method is demonstrated through three representative optimization examples: the cantilever beam, the special-shaped plate, and the S-shape shell. The study concludes that the proposed method can optimize arbitrary flat plates by embedding the design domain into the background domain. Additionally, the proposed method can be extended to perform stiffener design on complex surfaces by establishing projection relationship between the flat surface and the curved surface. Optimization results indicate that the non-uniform curved grid-stiffened shell design exhibits superior structural performance compared to the uniform grid-stiffened shell design. [ABSTRACT FROM AUTHOR]

This work presents a novel design of a low-profile broadband circularly polarized (CP) metasurface (MS) antenna based on characteristic mode analysis (CMA) technique for potential use in C-band satellite communications. The proposed antenna is composed of a 4 × 4 array of truncated patch unit cells and incorporates an enhanced slot coupling feeding structure. CMA technique is employed to analyse and modify to improved CP performance. The proposed design exhibits good radiation characteristics including measured − 10 dB impedance bandwidth of 22.72% (4.8–6.05 GHz), a 3 dB axial ratio bandwidth (ARBW) of 16.3% (5.1–5.95 GHz), and a peak gain of 8 dBi within its operational frequency range. Furthermore, the antenna's metasurface design contributes to scattering suppression over a wide frequency span (4–18 GHz), with a notable peak reduction of 9.1 dB at 8 GHz. This characteristic holds potential significance for radar cross-section (RCS) reduction. [ABSTRACT FROM AUTHOR]

A probabilistic approach to the epidemic evolution on realistic social-contact networks allows for characteristic differences among subjects, including the individual number and structure of social contacts, and the heterogeneity of the infection and recovery rates according to age or medical preconditions. Within our probabilistic Susceptible-Infectious-Removed (SIR) model on social-contact networks, we evaluate the infection load or activation margin of various control scenarios; by confinement, by vaccination, and by their combination. We compare the epidemic burden for subpopulations that apply competing or cooperative control strategies. The simulation experiments are conducted on randomized social-contact graphs that are designed to exhibit realistic person–person contact characteristics and which follow near homogeneous or block-localized subpopulation spreading. The scalarization method is used for the multi-objective optimization problem in which both the infection load is minimized and the extent to which each subpopulation's control strategy preference ranking is adhered to is maximized. We obtain the compounded payoff matrices for two subpopulations that impose contrasting control strategies, each according to their proper ranked control strategy preferences. The Nash equilibria, according to each subpopulation's compounded objective, and according to their proper ranking intensity, are discussed. Finally, the interaction effects of the control strategies are discussed and related to the type of spreading of the two subpopulations. [ABSTRACT FROM AUTHOR]

We consider the problem of evaluating designs for a small-sample two-arm randomized experiment using the power of the one-sided randomization test as a criterion. Our evaluation assumes a linear response in one observed covariate, an unobserved component and an additive treatment effect where the model's randomness is due to different treatment allocations. It is well-known that the power depends on the allocations' imbalance in the observed covariate. We show that power is additionally affected by two other design choices: the number of allocations and the degree of the allocations' dependence. We prove that the more allocations, the higher the power and the lower the variability in power. Our theoretical findings and simulation studies show that the designs with the highest power provide thousands of highly independent allocations each providing nominal imbalance in the observed covariates. These high-powered designs exhibit less randomness than complete randomization and more randomness than recently proposed designs that employ numerical optimization. This advantage of high power is easily accessible to practicing experimenters via the popular rerandomization design and a greedy pair switching design, where both outperform complete randomization and numerical optimization. The tradeoff we find also provides a means to specify rerandomization's imbalance threshold parameter. [ABSTRACT FROM AUTHOR]

In this paper, we propose a single photonic crystal structure to implement NOT/XOR/OR optical logic gates using interference phenomenon. The gates are designed as T-shaped waveguides. The filter rods used in the design enhance the contrast ratio by up to 82.25 dB compared with the existing designs reported in the literature so far, and provides a maximum bit rate of 1.567Tbps with a response time of 0.63 ps. The proposed design exhibits minimum power loss, and performance parameters are enhanced compared to existing reported works. Photonic logic gates emerged as a potential substitute for their traditional electronic counterparts due to quick speed, low power consumption, and compatibility with current optical communication networks. The size of the proposed device is 144 μm2, can be used for future optical computing and communications. [ABSTRACT FROM AUTHOR]

With the continuous development of rural revitalization and urbanization in China, the sustainable transformation of traditional rural architecture has become increasingly important. This study takes the Thangka exhibition hall in rural Malkang, Sichuan Province, as the research object and proposes a Thangka exhibition hall architectural design centered around solar heating and aiming for near-zero energy consumption. The research method involves establishing a solar energy system model on the roof of the exhibition hall and utilizing solar angle and area calculation formulas along with simulation software to calculate the optimal installation angle and area of solar panels, with the aim of achieving indoor temperatures that meet Thangka protection requirements while achieving zero-energy heating. Preliminary results indicate that this solar-centric near-zero energy architectural design can effectively promote the increase in indoor temperature through solar thermal conversion. Additionally, through calculation and simulation, the optimal installation angle for the solar panels achieving zero-energy heating is determined to be 24.25 with an azimuth angle of −1.2. The optimum installation area for solar panels is 8.2 square meters in the showroom and 2.7 square meters in the storeroom. Among these, the solar panel area for the Thangka exhibition hall constitutes 4.12% of the total area and is required for maintaining Thangka protection temperature requirements throughout the year, while the solar panel area for the storage room constitutes 1.88% and is also needed for the same purpose. Studying the optimal installation angle and area of solar panels can transform the exhibition hall into a near-zero-energy building, meeting the temperature requirements for Thangka preservation and human thermal comfort, while also achieving optimal economic benefits. This provides guidance and a reference for promoting near-zero-energy buildings in rural areas. [ABSTRACT FROM AUTHOR]

Topology optimization is one of the most flexible structural optimization methodologies. However, in exchange for its high level of design freedom, typical topology optimization cannot avoid multimodality, where multiple local optima exist. This study focuses on developing a gradient-free topology optimization framework to avoid being trapped in undesirable local optima. Its core is a data-driven multifidelity topology design (MFTD) method, in which the design candidates generated by solving low-fidelity topology optimization problems are updated through a deep generative model and high-fidelity evaluation. As its key component, the deep generative model compresses the original data into a low-dimensional manifold, i.e., the latent space, and randomly arranges new design candidates over the space. Although the original framework is gradient free, its randomness may lead to convergence variability and premature convergence. Inspired by a popular crossover operation of evolutionary algorithms (EAs), this study merges the data-driven MFTD framework and proposes a new crossover operation called latent crossover. We apply the proposed method to a maximum stress minimization problem in 2D structural mechanics. The results demonstrate that the latent crossover improves convergence stability compared to the original data-driven MFTD method. Furthermore, the optimized designs exhibit performance comparable to or better than that in conventional gradient-based topology optimization using the P-norm measure. [ABSTRACT FROM AUTHOR]

Extensive research is now being conducted on the design and construction of logic circuits utilizing quantum-dot cellular automata (QCA) technology. This area of study is of great interest due to the inherent advantages it offers, such as its compact size, high speed, low power dissipation, and enhanced switching frequency in the nanoscale domain. This work presents a design of a highly efficient RAM cell in QCA, utilizing a combination of a 3-input and 5-input Majority Voter (MV) gate, together with a 2 × 1 Multiplexer (MUX). The proposed design is also investigated for various faults such as single cell deletion, single cell addition and single cell displacement or misalignment defects. The circuit under consideration has a high degree of fault tolerance. The functionality of the suggested design is showcased and verified through the utilization of the QCADesigner tool. Based on the observed performance correlation, it is evident that the proposed design demonstrates effectiveness in terms of cell count, area, and latency. Furthermore, it achieves a notable improvement of up to 76.72% compared to the present configuration in terms of quantum cost. The analysis of energy dissipation, conducted using the QCAPro tool, is also shown for various scenarios. It is seen that this design exhibits the lowest energy dispersion, hence enabling the development of ultra-low power designs for diverse microprocessors and microcontrollers. [ABSTRACT FROM AUTHOR]

Deployable polyhedral grippers have attracted increasing attention for their priority in noncontact capturing missions. Enrichment of these grippers may benefit the conduction of various capturing tasks. In this paper, novel deployable polyhedral grippers are presented. A design flow is proposed for the structural designs of diverse grippers. The core problem during the construction is reducible to the structural designs and combination of multiple synchronously deployable modules. Each module, containing three faces connected by two revolute joints, can realize one-degree-of-freedom deployment. Type synthesis of synchronously deployable modules adopting different layouts of revolute joints is conducted. The mobility and kinematics of these modules are analyzed to verify the achieved motion. As examples, four deployable polyhedral grippers based on different polyhedrons and deployment diagrams are presented. The deployment performance of the prototype proves the validity of the proposed design method and exhibits the potential of these deployable polyhedral grippers for diverse capturing missions. [ABSTRACT FROM AUTHOR]

We numerically demonstrate three-octave supercontinuum generation using the z-cut lithium niobate waveguide by dispersion engineering. The photonic waveguide structure is designed to exhibit anomalous dispersion when pumped at 1.55 $ \rmu {\rm m} $ μ m wavelength. By altering the waveguide width, tunable zero-dispersion wave generation has been achieved up to 6 $ \rmu {\rm m} $ μ m wavelength. Our findings show the broadest supercontinuum spanning in the mid-IR region using a lithium niobate platform, making it a promising candidate for various applications in optical communication, sensing, and imaging. [ABSTRACT FROM AUTHOR]

Traditional methods of shielding fragile goods and human tissues from impact energy rely on isotropic foam materials. The mechanical properties of these foams are inferior to an emerging class of metamaterials called plate lattices, which have predominantly been fabricated in simple 2.5‐dimensional geometries using conventional methods that constrain the feasible design space. In this work, additive manufacturing is used to relax these constraints and realize plate lattice metamaterials with nontrivial, locally varying geometry. The limitations of traditional computer‐aided design tools are circumvented and allow the simulation of complex buckling and collapse behaviors without a manual meshing step. By validating these simulations against experimental data from tests on fabricated samples, sweeping exploration of the plate lattice design space is enabled. Numerical and experimental tests demonstrate plate lattices absorb up to six times more impact energy at equivalent densities relative to foams and shield objects from impacts ten times more energetic while transmitting equivalent peak stresses. In contrast to previous investigations of plate lattice metamaterials, designs with nonuniform geometric prebuckling in the out‐of‐plane direction is explored and showed that these designs exhibit 10% higher energy absorption efficiency on average and 25% higher in the highest‐performing design. [ABSTRACT FROM AUTHOR]

• Extended reality fosters artists, curators to frame and contextualize exhibitions. • Extended reality allow new conceptualizations of exhibiting art. • Ways of presenting art through extended reality can form a continuum with exhibits. • Extended reality exhibitions interrelate media design, aims/scope and content. This manuscript addresses the increasing importance of Extended Reality (XR) in art exhibitions. It elaborates on the technologies employed, design issues, pertinent aims, and evaluation metrics. The main research questions concern the types of technologies currently used, the primary design considerations, and the ways user experience can be enhanced in accordance with the artists' and curators' vision, as well as visitors' needs. Moreover, the paper also examines relevant evaluation criteria. The manuscript reviews the types of technologies used for virtual art exhibitions and examines their design characteristics and pertinent issues on interfaces, resources, and affordances. Furthermore, an analysis of the use of virtual humans as a model for increased engagement follows a discussion of a comparison between virtual versus physical exhibitions. Moreover, the parameters that affect user experience are discussed thoroughly, given their pivotal importance in such exhibitions. Finally, the paper concludes with a discussion of the above-mentioned aspects of XR exhibitions with an emphasis on optimizing design for art-related content and offering informed suggestions for future directions. The overall scope of this paper is to examine ways to exploit XR as a creative medium rather than merely replicate physical exhibitions. In this context, the papers' discussion includes the Metaverse. [ABSTRACT FROM AUTHOR]

Past research that investigated the behaviour of rectangular lightly reinforced concrete walls resulted in revisions to minimum vertical reinforcement provisions in concrete design standards in both New Zealand (NZS 3101:2006) and the United States (ACI 318-19). However, the minimum vertical reinforcement provisions developed for rectangular wall sections may not be suitable for non-rectangular walls due to the influence of flanges on the nominal flexural and cracking section capacities. A parametric study confirmed that non-rectangular wall sections with minimum vertical reinforcement in accordance with current NZS 3101 design provisions exhibit a lower margin between cracking and nominal flexural strength than comparable rectangular wall sections. The ratio of the sectional nominal flexural strength to cracking strength (Mn/Mcr) was less than 1.0 for non-rectangular sections with long flange lengths and low axial loads. The model results indicated that current vertical reinforcement requirements are insufficient to prevent a sudden and potentially unstable strength drop when cracking occurs in non-rectangular walls. A theoretical equation to calculate the required minimum vertical reinforcement was proposed for the typical I-shaped wall sections, including the impact of concrete strength and flange to web ratio. The proposed equation highlighted the need for an increase in the minimum vertical reinforcement limits for non-rectangular wall sections compared to the existing minimum vertical reinforcement requirement applicable to rectangular wall sections. [ABSTRACT FROM AUTHOR]

Today's ever‐increasing generation of streaming data demands novel data mining approaches tailored to mining dynamic data streams. Data streams are non‐static in nature, continuously generated, and endless. They often suffer from class imbalance and undergo temporal drift. To address the classification of consecutive data instances within imbalanced data streams, this research introduces a new ensemble classification algorithm called Rarity Updated Ensemble with Oversampling (RUEO). The RUEO approach is specifically designed to exhibit robustness against class imbalance by incorporating an imbalance‐specific criterion to assess the efficacy of the base classifiers and employing an oversampling technique to reduce the imbalance in the training data. The RUEO algorithm was evaluated on a set of 20 data streams and compared against 14 baseline algorithms. On average, the proposed RUEO algorithm achieves an average‐accuracy of 0.69 on the real‐world data streams, while the chunk‐based algorithms AWE, AUE, and KUE achieve average‐accuracies of 0.48, 0.65, and 0.66, respectively. The statistical analysis, conducted using the Wilcoxon test, reveals a statistically significant improvement in average‐accuracy for the proposed RUEO algorithm when compared to 12 out of the 14 baseline algorithms. The source code and experimental results of this research work will be publicly available at https://github.com/vkiani/RUEO. [ABSTRACT FROM AUTHOR]

A differential ring CMOS voltage-controlled oscillator (VCO) with dual-delay path topology is proposed in this paper. In this work, the focus area is to improve the tuning range of VCO and phase noise performance of the VCO. The dual-delay path topology is used with P-MOS as load in series with negative-skewed delay transistors. This design gives the wider tuning range and this increases the phase noise performance of the VCO. After the post-layout simulation, frequency tuning range and power dissipation range are 730 MHz to 2.81 GHz and from 1.32 mW to 4.62 mW respectively. The phase noise for this VCO is −97.35 dBc/Hz at 1 MHz offset. The technology used in this work was taken from the library of SCL 180 nm technology. This design exhibits excellent phase noise performance. [ABSTRACT FROM AUTHOR]

Ultra-high performance concrete (UHPC) is a durable and versatile construction material that enables the engineering of slender fabricated beams. Nonetheless, existing design methodologies exhibit certain discrepancies in predicting the ultimate shear capacity of UHPC beams. This study aimed to develop an improved predictive shear model based on design and mechanical properties. Eleven prestressed rectangular UHPC beams were subjected to shear tests, systematically investigating essential design parameters such as shear-span-to-depth ratio, stirrups ratio, longitudinal reinforcement ratio, prestressing force, and prestressing type. The results demonstrated that UHPC beams exhibit strain-hardening behavior after cracking, accompanied by the formation of dense diagonal cracks. Localized cracking eventually led to shear failure. The shear behavior was primarily influenced by the shear-span-to-depth ratio, showing an inverse relationship with shear strength. Increasing the longitudinal reinforcement ratio, stirrups ratio, and prestressing force marginally improved shear capacity. Furthermore, a limit equilibrium state-based method was proposed to develop a practical prediction formula that incorporates steel fibers and matrix interaction. The proposed method demonstrated superior accuracy compared to existing design models, displaying an average difference of 1.1% and a correlation coefficient of 0.96 with experimental results. [ABSTRACT FROM AUTHOR]

Hybrid metasurfaces are made of metals and dielectrics in which dielectrics (metals) are sandwiched between metals (dielectrics) to control the reflection and transmission of light. The existing designs have low sensitivity, little color coverage, and a lack of flexibility. Here, a new structural color design is proposed in which metals and dielectric resonators are arranged spatially in 2D to form a lateral hybrid system, instead of being placed as layers. Such a design exhibits a high level of sensitivity to mechanical forces because it works via 2D optical coupling and light confinement between adjacent resonators. Our study shows that in-planar coupling of two dissimilar resonators can enhance sensitivity by an order of magnitude in comparison to stacking them. Metasurfaces with our design would have unprecedented mechanical tunability without compromising either the materials choice or processing. Using the proposed hybrid system, we demonstrate large tunability across the full range of colors with only a 10% change in the size of the lattice, which further proves its superiority over existing designs. This concept could find application in wearable devices that require high sensitivity to small mechanical fluctuations. [ABSTRACT FROM AUTHOR]

We present an experimental study of plasmonic slanted slit gratings (PSSGs) designed to achieve directional coupling between an incident light beam and surface plasmon polaritons (SPPs) propagating along the surface of the structure. We also investigate mirrored PSSG pairs interconnected by a plasmonic slab waveguide. The structures are fabricated using direct milling by a gallium focused ion beam (FIB). In a mirrored pair arrangement, the first PSSG couples a perpendicularly-incident light beam to SPPs propagating in one direction along the waveguide, while the second PSSG decouples SPPs to perpendicularly-emerging light. This configuration shows promise for sensing applications due to the high sensitivity of the excited SPPs to changes in the refractive index of the bounding medium, and the separation of the optics from the fluidics by the substrate. The design also exhibits robustness to fabrication tolerances. The optical characteristics and sensing potential are investigated theoretically and experimentally, highlighting its potential for a wide range of applications. [ABSTRACT FROM AUTHOR]

PURPOSE: The way late-onset toxicities are managed can affect trial outcomes and participant safety. Specifically, participants often might not have completed their entire follow-up period to observe any toxicities before new participants would be recruited. We conducted a methodological review of published early-phase dose-finding clinical trials that used designs accounting for partial and complete toxicity information, aiming to understand (1) how such designs were implemented and reported and (2) if sufficient information was provided to enable the replicability of trial results. METHODS: Until March 26, 2023, we identified 141 trials using the rolling 6 design, the time-to-event continuous reassessment method (TITE-CRM), the TITE-CRM with cycle information, the TITE Bayesian optimal interval design, the TITE cumulative cohort design, and the rapid enrollment design. Clinical settings, design parameters, practical considerations, and dose-limiting toxicity (DLT) information were extracted from these published trials. RESULTS: The TITE-CRM (61, 43.3%) and the rolling 6 design (76, 53.9%) were most frequently implemented in practice. Trials using the TITE-CRM had longer DLT assessment windows beyond the first cycle compared with the rolling 6 design (52.5% v 6.6%). Most trials implementing the TITE-CRM (91.8%, 56 of 61) failed to describe essential parameters in the protocols or the study result papers. Only five TITE-CRM trials (8.2%, 5 of 61) reported sufficient information to enable replication of the final analysis. CONCLUSION: When compared with trials using the rolling 6 design, those implementing the TITE-CRM design exhibited notable deficiencies in reporting essential details necessary for reproducibility. Inadequate reporting quality of advanced model-based trial designs hinders their credibility. We provide recommendations that can improve transparency, reproducibility, and accurate interpretation of the results for such designs. Evaluated late-onset toxicity-focussed dose-finding trials, recommending improved reporting practices [ABSTRACT FROM AUTHOR]

In this article, we demonstrated the minimum significant dielectric thickness of silicon dioxide (SiO2) below the diffraction limit for the confinement in the metal–insulator–metal (MIM) waveguide and utilizing this idea, we further exhibited the detail design analysis of dual‐band plasmonic meandering step impedance resonator (MSIR), which can achieve a high quality‐factor compared to a traditional step impedance resonator (SIR). MSIRs have sharper wavelength selectivity compared to SIRs, making them more suitable for applications that require precise wavelength tuning. The tunability of reflection and transmission characteristics with respect to design parameters has been reported. The designed MSIR has demonstrated a good passband response at wavelengths λ = 1414‐nm (E‐band) and 1577‐nm (L‐band) as well as turnability with design parameters. This filter achieved a large frequency spectral range of 139 nm and a high Q factor of ~3 × 104. This work enhances the capability of on‐chip filtering in the plasmonic platform. [ABSTRACT FROM AUTHOR]

Optical computers, leveraging the advantages of light characteristics, hold the potential to outperform electronic computers significantly. The role of all‐optical logic gates is pivotal in realizing such high‐performance computing systems. This research introduces a streamlined design for an all‐optical NOR logic gate utilizing a semiconductor optical amplifier. The proposed gate operates at a remarkable data rate of 40 Gbps, achieving an excellent extinction ratio of 20.285 dB. Notably, the design exhibits very low dispersion (−0.029 × 10+006 ps/nm) and an impressively low bit error rate of 4.27 × 10−26. [ABSTRACT FROM AUTHOR]

In this letter, a wide stopband quarter‐mode substrate‐integrated waveguide (QMSIW) diplexer is proposed. By using coupling feeding lines and QMSIW cavities, the two passbands of the diplexer can be controlled independently by their respective QMSIW bandpass filters. In comparison to other counterparts, the proposed diplexer provides flexible passband specification, compact size, and high isolation. The design exhibits a wide 20‐dB stopband up to 3.2f0, a frequency ratio of 1.6, and a high isolation level larger than 42.2 dB across the passbands. [ABSTRACT FROM AUTHOR]

The Rijksmuseum in Amsterdam held a major exhibition of the artwork of Johannes Vermeer from February 10 to June 4, 2023. Twenty-eight of his paintings were gathered in one place, the largest exhibition ever of his oeuvre. The author not only went to this exhibition but also traveled to Vermeer's hometown of Delft where the artist spent almost his entire life. In addition to reviewing the design and layout of the exhibition as well as the art shown, he discusses the importance of Delft as a location along with significant events in Dutch history at that time. The psychological effects of looking at Vermeer are considered, with attention to Vermeer's use of colors, perspective, themes, and light. Vermeer's capacity for opening an observer to introversion is elaborated through a discussion of the archetypal dimensions of his art as well as his innovative understanding of how to represent pregnant moments. [ABSTRACT FROM AUTHOR]

In the past decade, photonic integrated circuits (PICs) based on thin-film lithium niobate (TFLN) have made substantial progress in various fields, including optical communication, nonlinear photonics, and quantum optics. A critical component is an efficient edge coupler facilitating the connection between PICs and light sources or detectors. Here, we propose an innovative edge coupler design with a wedge-shaped TFLN waveguide and a silicon oxynitride cladding. Experimental results show a low coupling loss between the TFLN PIC and a 3-μm mode field diameter (MFD) lensed fiber, measuring at 1.52 dB/facet, with theoretical potential for improvement to 0.43 dB/facet. Additionally, the coupling loss between the edge coupler and a UHNA7 fiber with an MFD of 3.2 μm is reduced to 0.92 dB/facet. This design exhibits robust fabrication and alignment tolerances. Notably, the minimum linewidth of the TFLN waveguide of the coupler (600 nm) can be readily achieved using commercially available i-line stepper lithography. This work benefits the development of TFLN integrated devices, such as on-chip electro-optic modulators, frequency combs, and lasers. [ABSTRACT FROM AUTHOR]

Layered transition metal dichalcogenides have great potential as anodes of sodium‐ion batteries (SIBs) due to their high theoretical specific capacity. However, the restacking severely limits their accessible sites, leading to undesirable specific capacity, cycle stability, and working temperature range. Herein, a hierarchical 2D VS2/Ti3C2Tx MXene hybrid is designed via a simple liquid‐mixing method, where VS2 is confined in the conductive Ti3C2Tx matrix with chemical connections built between them. The in situ transmission electron microscopy analyses reveal that the hybrid depends on a very fast and reversible intercalation/de‐intercalation process between VS2 and NaxVS2 (where x = 1) to store sodium. Theoretical calculations disclose that the Ti3C2Tx matrix remarkably enhances the charge transfer and alleviates the volume expansion of VS2 especially after Na+ is inserted. Consequently, such a rational design exhibits an intercalation pseudocapacitance‐dominant mechanism, with excellent specific capacity (522 mAh g−1 at 0.2 A g−1), rate capability (342 mAh g−1 at 10 A g−1), cycle life (116% after 3000 cycles), and also all‐climate workability (with high specific capacity and long‐term cycle stability even at 70 and −40 °C). This study may open up a new vision to design fast‐charging, long‐cycle, and all‐climate SIBs anodes based on the intercalation pseudocapacitance. [ABSTRACT FROM AUTHOR]

This work focused on the novel symmetrical left-handed split ring resonator metamaterial for terahertz frequency applications. A compact substrate material known as Silicon with a dimension of 5 µm was adopted in this research investigation. Moreover, several parameter studies were investigated, such as clockwise rotation, array and layer structure designs, larger-scale metamaterials, novel design structure comparisons and electric field distribution analysis. Meanwhile, two types of square-shaped metamaterial designs were proposed in this work. The proposed designs exhibit double and single resonance frequencies respectively, likely at 3.32 and 9.24 THz with magnitude values of − 16.43 and − 17.33 for the first design, while the second design exhibits a response at 3.03 THz with a magnitude value of − 19.90. Moreover, the verification of these results by adopting High-frequency Structure Simulator software indicates only slight discrepancies which are less than 5%. Furthermore, the initial response of the proposed designs was successfully altered by simply rotating the design clockwise or even increasing the dimension of the design. For instance, the first resonance frequency is shifted to the lower band when the first proposed design was rotated 90°. On the other hand, by increasing the size of the metamaterial, more than nine resonance frequencies were gained in each symmetric design. Furthermore, the symmetric metamaterial with a similar width and length of 10 µm dimension was adopted for both design structures to construct an equivalent circuit model by utilising Advanced Design System software. Finally, both unit cell designs were utilised to explore the absorption performances which exhibit four and five peak points. Overall, the altering behaviour by changing physical properties and compact design with acceptable responses become one of the novelties of this research investigation. In a nutshell, the proposed designs can be utilised in terahertz frequency which gives optimistic or advantageous feedback and is relatively suitable for the adopted frequency range. [ABSTRACT FROM AUTHOR]

Tilted tongue is one of the very effective solutions to reduce the noise of centrifugal fans. In this study, the accuracy of the numerical simulations is verified by experimentally measured aerodynamic performance and acoustic spectra. Two localized tilting designs of the tongue are proposed with the aim of reducing the aerodynamic noise of the centrifugal fan. Numerical results show that the different approaches significantly affect the noise reduction of the fan, with the best design exhibiting up to 2.33 dB of noise reduction. The internal flow and acoustic fields are analyzed in conjunction with the dynamic modal decomposition method to reveal the effect of the local tilt of the tongue on the flow and acoustic characteristics of the fan. The structural change induces the separation vortices at the trailing edge of the blades and the generation of secondary flow at the outlet wall of the volute shell, which is the main reason for the slight degradation of the aerodynamic characteristics of the fan. The causes of the blade passage frequency (BPF) noise reduction are not identical for different orders. BPF noise reduction stems from diminishing source intensity and dispersing source phase. Noise reduction in 2BPF is mostly due to weakening sound source intensity, with less conspicuous phase dispersion. This study provides good theoretical support for the design of backward curved centrifugal fans in the context of noise reduction. [ABSTRACT FROM AUTHOR]

Recently, artificial perforated auxetic metastructures with negative Poisson's ratio have attracted considerable attention with the superior mechanical properties. The concepts and design methods of various types of perforated auxetic metastructures have developed rapidly. However, the effective Poisson's ratio exhibited by the majority of current perforated auxetic metastructures has a lower limit of −1, which restrains their potential applications significantly. Herein, a novel 2D perforated auxetic metastructure is proposed by arraying orthogonal barbell‐shaped holes onto a sheet structure. The mechanical properties and the underlying deformation mechanism of the proposed auxetic metastructure are then investigated by performing experimental tests and finite element simulations. Results show that the lower limit of the Poisson's ratio exhibited by the proposed auxetic metastructure surpasses −1 remarkably and the proposed design hence exhibits much better auxetic performance compared with existing designs. It is also revealed that the proposed design exhibits relatively low local stress distribution. The results of this study will broaden the potential applications of perforated auxetic metastructures in many engineering fields. [ABSTRACT FROM AUTHOR]

'Live minting' is an emerging trend in exhibition design which offers visitors the opportunity to mint an NFT memento in the exhibition. This paper examines three examples of this current trend in museums which include Play Record Mint (PRM), at Kunsthalle, Zurich, Life After Bob at Light Art Space (LAS) Foundation, Berlin, and Unsupervised at Museum of Modern Art (MoMA), New York. Using theories on the 'museum experience' drawn from scholars such as John Falk and Lynn Dierking (2011; 1992; 2008), this paper examines to what extent the NFTs in these examples contribute or challenge this idea. In doing so, this paper investigates the intersecting values associated with NFTs and argues that NFTs are a form of digital hybrid, a token that exists in a constant state of becoming a commodity, which has both potential benefits and implications for museum exhibition design. [ABSTRACT FROM AUTHOR]

Where economists previously viewed the market as arising from a ‘spontaneous order’, antithetical to design, they now design markets to achieve specific purposes. This paper reconstructs how this change in what markets are and can do came about and considers some consequences. Two decisive developments in economic theory are identified: first, Hurwicz’s view of institutions as mechanisms, which should be designed to align incentives with social goals; and second, the notion of marketplaces – consisting of infrastructure and algorithms – which should be designed to exhibit stable properties. These developments have empowered economists to create marketplaces for specific purposes, by designing appropriate algorithms. I argue that this power to create marketplaces requires a shift in ethical reasoning, from whether markets should reach into certain spheres of life, to how market algorithms should be designed. I exemplify this shift, focusing on bias, and arguing that transparency should become a goal of market design. [ABSTRACT FROM AUTHOR]

Proximity‐fed compact wideband rectangular and circular microstrip antennas by employing H‐shape, C‐shape, and W‐shape ground plane profiles are proposed. Optimum results are obtained in rectangular microstrip antenna using H‐shape ground plane. Against the conventional ground plane, it gives 16% bandwidth improvement, supported by 17.29% and 31% reduction in resonant mode frequency and patch area, respectively. The proposed design exhibits a broadside pattern with a gain of 6.1 dBi and can find applications in GSM 900 band. [ABSTRACT FROM AUTHOR]

The majority of injuries and deaths are caused by a vehicle accident in the front structure. This research endeavours to systematically refine bumper beam structures through an amalgamation of computational simulations, advanced material selection, and experimental validations. A multifaceted approach is employed, encompassing finite element analysis (FEA) techniques to model and predict crash responses, coupled with iterative design iterations to optimize energy absorption and deformation characteristics. The study delves into the synergistic effects of material properties, geometric parameters, and structural arrangements on crash performance. The results underscore the intricate interplay between structural rigidity, energy absorption, and occupant safety. This work entails designing a car bumper beam in the W section that could withstand a low-impact collision with a new energy absorbing material. The optimized designs exhibit superior crashworthiness metrics, highlighting the potential to significantly mitigate collision-induced forces. This study underscores the imperative for continuous exploration and innovation in bumper beam design to elevate vehicular safety standards and ultimately reduce the human and economic toll of road accident. [ABSTRACT FROM AUTHOR]

We present a versatile THz waveguide platform for frequencies between 0.1 THz and 1.5 THz, designed to exhibit vacuum-like dispersion and electric as well as magnetic field enhancement. While linear THz spectroscopy benefits from the extended interaction length in combination with moderate losses, nonlinear THz spectroscopy profits from the field enhancement and zero dispersion, with the associated reshaping-free propagation of broadband single- to few-cycle THz pulses. Moreover, the vacuum-like dispersion allows for velocity matching in mixed THz and visible to infrared pump-probe experiments. The platform is based on the motif of a metallic double ridged waveguide. We experimentally characterize essential waveguide properties, for instance, propagation and bending losses, but also demonstrate a junction and an interferometer, essentially because those elements are prerequisites for THz waveform synthesis, and hence, for coherently controlled linear and nonlinear THz interactions. [ABSTRACT FROM AUTHOR]

The pavilion combines multi-modal interaction based on Time-Division Long Term Evolution (TD-LTE) to increase the exhibition's interactivity and attractiveness with development of digital technology. Multi-modal interaction enables consumers to engage easily and intuitively with exhibitions or display material with the use of a touch screen, voice recognition, posture detection, and other interactive tools for immersive displays. This paper investigates the construction of a multi-modal interactive exhibition space using digital media technology. In contrast to the usual data collection techniques, which are costly, deficient in 3D pictures, suffer from a lack of spatial position data, and have other drawbacks, key techniques such as deep learning and posture estimation employed in immersive displays sometimes require huge training datasets to enhance the generality of the models. A 6D network architecture for target object estimation is proposed in this research to lower the cost of data collection. The interactive experience of visitors in the exhibition space, exhibit display, and exhibition space management can be improved by multi-modal interaction based on TD-LTE. Visitors can peruse exhibit material, watch movies, and play interactive games more freely due to the engagement modes. Exhibition managers may optimize the layout of the exhibition space and the placement of the exhibits through real-time monitoring, data collection, and analysis. The multi-mode interaction mode based on TD-LTE wireless communication technology can give visitors a rich and more user-friendly exhibition experience with a wide range of application prospects and potentials. [ABSTRACT FROM AUTHOR]

This article proposes a design strategy for acoustic metamaterial lattices which leverages the characteristic multi-stability and kinematic amplification of the internal architecture to realize a re-configurable effective mass distribution, enabling a corresponding frequency band structure of extreme tunability. The approach builds metamaterial lattices from bi-stable elastic elements featuring the typical two-bar inertial amplification mechanism, whose deformation axis is uniquely misaligned with that of its elastic support such that the realized amplification is configuration-specific. Conveniently, a change in the configuration does not simultaneously alter the element dimensions and, therefore, the size/shape of the finite metamaterial structure remains constant. Moreover, as the multi-stability and kinematic amplification are each based on geometry, scaling the resulting metamaterial structure is expected to be straightforward. The dynamic performance of 1D/2D metamaterial architectures exhibiting the proposed design strategy is analytically determined via Bloch wave analysis and supported by numerical demonstration of the corresponding finite structures. [ABSTRACT FROM AUTHOR]

Recent advances in wearable devices have enabled noninvasive monitoring for healthcare applications. Smart contact lenses have gained substantial attention for medical diagnosis through the analysis of vital signs in tear fluids. However, previous studies have mostly focused on designs embedded with electronic devices or antennas for wireless transmission, which are power‐intensive and require external receivers around the ocular system. Here, the study reports a power‐free smart contact lens for noninvasive glucose sensing according to the color changes of multiple electrochromic electrodes to achieve direct data transmission without the external wireless system. The device detects various glucose concentrations, from the ordinary range (0.16–0.5 mm) to abnormally high concentrations (0.9 mm). The multi‐electrode design exhibits acceptable accuracy, with a correlation coefficient r = 0.99543 to the controlled sample and allowed low‐glucose detections with concentrations down to 0.05 mm. The device shows good reproducibility, with standard deviations of determined glucose levels of 0.0462 and 0.025 for four continuous cycles and for an interval of several days, respectively. It is believed that the reported smart contact lens has the potential for daily health monitoring by ordinary users without a power supply and external devices. Its simple electronics‐free structure will allow for immediate application to the market with cost‐effective manufacturing. [ABSTRACT FROM AUTHOR]

The encapsulation of a rigid core within a soft polymeric shell allows obtaining composite colloidal particles that retain functional properties, e.g., optical or mechanical. At the same time, it favors their adsorption at fluid interfaces with a tunable interaction potential to realize tailored two‐dimensional (2D) materials. Although they have already been employed for 2D assembly, the conformation of single particles, which is essential to define the monolayer properties, has been largely inferred via indirect or ex situ techniques. Here, by means of in situ atomic force microscopy experiments, the authors uncover the interfacial morphology of hard‐core soft‐shell microgels, integrating the data with numerical simulations to elucidate the role of the core properties, of the shell thicknesses, and that of the grafting density. They identify that the hard core can influence the conformation of the polymer shells. In particular, for the case of small shell thickness, low grafting density, or poor core affinity for water, the core protrudes more into the organic phase, and the authors observe a decrease in‐plane stretching of the network at the interface. By rationalizing their general wetting behavior, such composite particles can be designed to exhibit specific inter‐particle interactions of importance both for the stabilization of interfaces and for the fabrication of 2D materials with tailored functional properties. [ABSTRACT FROM AUTHOR]

Wideband beamformers have been widely studied in wireless communication, remote sensing and so on. Generally speaking, to improve the spatial filtering ability of beamformers, there usually needs more sensors, which implies increased computational complexity and hardware costs. Besides that, wideband beamformers are known to be exceedingly sensitive to sensor mismatches in practice. Nevertheless, there is still a gap in research on the design of robust sparse wideband beamformers. In this paper, a two-step design of this topic is proposed. Firstly, a robust design based on the worst-case performance optimization (WCPO) using circular-model (CM) sensor mismatches is reformulated to address shortcomings of constraint sensitivity. Secondly, inspired by the joint sparse technology in compressive sensing theory, we focus on the sparse design of wideband beamformer. The constraints for the response characteristics and robustness are set from first step, and an iterative algorithm based on reweighted ℓ 2 , 1 optimization is adopted to achieve maximum sparsity of the sensor array. The mainly advantages of the work are that the proposed design exhibits accordant performance in terms of response and robustness, but few sensors compared with the counterpart with uniform array. Moreover, we surprisingly find that the optimized sparse array is also applicable to other design based on WCPO criterion. Simulation results are provided to verify the superior of the proposed methods compared to the existing counterparts. [ABSTRACT FROM AUTHOR]

Summary: In light of the increasing share of renewable energy sources (RES) in electricity generation, the research community is directing their attention toward developing highly efficient DC‐DC high‐gain step‐up converters. These converters are designed to exhibit reduced voltage stress on the switching devices (semiconductors). This paper presents a comprehensive study of a switch voltage stress‐reduced step‐up converter that offers a range of additional features, including the availability of a common ground point, continuous input current, simple two‐mode continuous conduction mode (CCM) operation, wide duty cycle range, and quadratic boosting factor. To achieve the aforementioned features, the converter utilizes two switches with the same operating modes, eliminating the need for complex switching circuitry. Operational modes, steady‐state analysis, and design considerations have been presented in detail. Comparative analysis indicates that the voltage conversion ratio per number of devices in the proposed topology is significantly higher than that of similar topologies. In addition, the voltage stress of switches is considerably less than the topologies addressed in the literature. The study further includes detailed mathematical and experimental analyses, small signal analysis, and hardware implementation to support the theoretical findings. The converter's efficiency has been thoroughly analyzed along with thermal analysis to ensure its reliability. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to show that due to the emergence of the Internet of Things (IoT) industry in recent years, the demand for the higher integration of wireless communication systems with a higher data rate of transmission capacity and lower power consumption has increased tremendously. The radio frequency power amplifier (PA) design is getting more challenging and crucial. A PA for a 2.45 GHz IoT application using 0.18 µm complementary metal oxide semiconductor (CMOS) technology is presented in this paper. Design/methodology/approach: The design consists of two stages, the driver and output stage, where both use a single-stage common source transistor configuration. In view of performance, the PA can deliver more than 20 dB gain from 2.4 GHz to 2.5 GHz. Findings: The maximum output power achieved by PA is 13.28 dBm. As the PA design is targeted for Bluetooth low energy (BLE) transmitter use, a minimum of 10 dBm output power should be achieved by PA to transmit the signal in BLE standard. The PA exhibits a constant output third-order interception point of 18 dBm before PA becomes saturated after 10 dBm output power. The PA shows a peak power added efficiency of 17.82% at the 13.24 dBm output power. Originality/value: The PA design exhibits good linearity up to 10 dBm out the PA design exhibits good linearity up to 10 dBm output power without sacrificing efficiency. At the operating frequency of 2.45 GHz, the PA exhibits a stability k-factor, the value of more than 1; thus, the PA design is considered unconditional stable. Besides, the PA shows the s-parameters performance of –7.91 dB for S11, –11.07 dB for S22 and 21.5 dB for S21. [ABSTRACT FROM AUTHOR]

Several recent studies have discussed approaches to planning and implementing digital exhibitions in libraries. However, prominent library organizations such as the American Library Association and IFLA have no published best practices or standards for digital exhibitions. The literature shows that digital exhibitions and digital supplements to in-person exhibits have benefits, including increased accessibility and user engagement. Using interviews with professionals at information institutions, this paper reveals and clarifies the common practices used to create digital exhibitions and the challenges of the design process. Additional interviews with professors of religious studies who utilize digital exhibits and resources in their roles as educators provide insight into the use of digital exhibits as tools for expanding public understanding of important historical and cultural topics. The consensus of creators and users of digital exhibitions is that they are valuable educational resources that reach new users, provide additional context for materials, and increase user engagement. [ABSTRACT FROM AUTHOR]

The unique ability to absorb electromagnetic radiation by metamaterial absorbers has garnered significant attention in recent periods. The proposed simulation study shows a new SRR-based metamaterial absorber design which has potential applications in biological sensing operating in the terahertz range. The proposed design incorporates four identical square ring resonators (SRR) made from Tungsten placed on top of a dielectric layer that was made by Gallium Arsenide (GaAs) semiconductor. Both the layers are formed on a Silicon substrate. The sensing regime's high field confinement results in a unity perfect absorption (i.e.,100%) at 2.75 THz, with a large quality factor of 39. According to the findings, the proposed design exhibits exceptional sensitivity while modifying the refractive index (n) of the medium. As a result, the proposed device can serve as a biomedical sensor (refractive index (n) sensor) with a sensitivity of 60 THz/RIU and a figure of merit (FoM) of 20. The researchers verified the device with refractive index (n) values ranging from 1.34 to 1.39, which covers a broad range of biomedical blood samples, including cancerous cells. As a result, this sensor design can be employed for a variety of biomedical sensing applications. [ABSTRACT FROM AUTHOR]

The rapid growth in the miniaturized mechanical and electronic devices industry has created the need for temporary attachment systems that can carry out pick‐and‐place and transfer printing tasks for fragile and tiny parts. Current systems are limited by a fundamental trade‐off between adhesive strength and state‐changing trigger force, which causes the need for a rapidly switchable adhesive. In this study, an elastomeric microstructure is presented combining a trapezoidal‐prism‐shaped (TPS) and a mushroom‐shaped microstructure, which overcomes the trade‐off with the help of the TPS structure. The optimal design exhibits a strong adhesive strength of 87.8 kPa and a negligible detachment strength of <0.07 kPa with a low trigger shear stress of 10.7 kPa on smooth glass surfaces. The large tip‐to‐stem ratio (50 to 20 µm) enhances the suction effect, allowing the microstructure to maintain its adhesive performance even in wet conditions. Pick‐and‐place manipulation tasks of a single and an array of ultralight parts from micrometer to millimeter scales are performed to demonstrate the capability of handling fragile and tiny parts. Moreover, it demonstrates the ability to transfer parts across water and air interfaces. This proposed microstructure offers a facile solution for manipulating microscale fragile parts in dry and wet conditions. [ABSTRACT FROM AUTHOR]