Active acoustic metamaterials consisting of sensor and driver elements that produce a programmed response to impinging acoustic waves have been widely considered an appealing way to overcome the fundamental shortcomin...
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Active acoustic metamaterials consisting of sensor and driver elements that produce a programmed response to impinging acoustic waves have been widely considered an appealing way to overcome the fundamental shortcomings of passive structures. However, research into active metamaterials has been hindered by their potential instability resulting from very complex interactions between cells and the lack of realistic stability models taking these interactions into account. We present a general method for assessing the stability of active metamaterials of arbitrary geometry and number of cells and show that stability imposes previously unknown limitations on the realizable acoustic properties. We validate the theory by accurately predicting the bounds on the realizable effective properties of an experimental metamaterial.
Although the triboelectric nanogenerator(TENG)has been highlighted as a promising mechanical energy harvester,the requirement of stacking the two individual layers,contact and conductive layers,has been ball and chain...
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Although the triboelectric nanogenerator(TENG)has been highlighted as a promising mechanical energy harvester,the requirement of stacking the two individual layers,contact and conductive layers,has been ball and chain around the ankle of unleashing potential and an advantage of TENGs in their application expansion and ***,one-step fabrication of a single-layered bifunctional composite film-based TENG(BFTENG)driven by the sedimentation of a sol-state precursor is proposed for the extremely facile conversion of various ordinary items into energy *** BF-TENG consists of the polydimethylsiloxane(PDMS)matrix and a carbon nanopowder filler,and it includes both the dielectric part(DP)and conductive part(CP)in one single *** electrical percolation threshold of the incorporated concentration of carbon,ICC,for CP to act as a passage through which induced charges move in BF-TENGs is determined to be 1.0 wt%.The degree of carbon sedimentation in developing the proposed composite can be controlled by the curing speed and the probability of a crosslinking *** maximum peak power is approximately 0.093μW when the contact surface area is 78.5 mm2;the contact frequency is 8 Hz,and the connected load resistance is 9 MΩ.Based on these results,the electrical performance of BF-TENGs in response to various physical stimuli is characterized considering the mechanical energy sources available in daily ***,converting ordinary surfaces such as desks and human skin into BF-TENGs through a single coating procedure and harvesting energy to power an electric device are demonstrated as a proof-of-concept.
The mechanical and corrosion characteristics of aluminum alloys can be influenced not only by the addition of grain refiners but also by heat treatment that modifies the microstructure and introduces variations in the...
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Nowadays, Industry 4.0 will become urgently implemented in most developed countries, although it is still mainly conceptual. As there are three different aspects making up Industry 4.0 (I4.0), such as digital systems,...
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Fe-based alloys have recently become well-known for their ability to resist wear and corrosion. Iron, the primary component of alloys, is a cheaper option than alloys made from Co and Ni. There is a need for affordabl...
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Immersion of scaffolds in Simulated Body Fluid(10SBF)is a standardized method for evaluating their bioactivity,simulating in vivo conditions where apatite deposits can be formed on the surface of scaffold,facilitating...
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Immersion of scaffolds in Simulated Body Fluid(10SBF)is a standardized method for evaluating their bioactivity,simulating in vivo conditions where apatite deposits can be formed on the surface of scaffold,facilitating bone integration and ensuring their suitability for bone implant purposes,ultimately contributing to long-term implant *** effect of apatite deposition on bioactivity and cell behavior of TiO_(2)scaffolds was *** were soaked in 10SBF for different durations to form HAP layer on their *** results proved the development of a hydroxyapatite film resembling the mineral composition of bone Extracellular Matrix(ECM)on the TiO_(2)*** XRD test findings showed the presence of hydroxyapatite layer similar to bone at the depth of 10 nm.A decrease in the specific surface area(18.913 m^(2)g^(−1)),the total pore volume(0.045172 cm^(3)g^(−1)(at p/p0=0.990)),and the mean pore diameter(9.5537 nm),were observed by BET analysis which confirmed the formation of the apatite *** was found that titania scaffolds with HAP coating promoted human osteosarcoma bone cell(MG63)cell attachment and *** seems that immersing the scaffolds in 10SBF to form HAP coating before utilizing them for bone tissue engineering applications might be a good strategy to promote bioactivity,cell attachment,and implant fixation.
Advanced Air Mobility(AAM)has emerged as a pioneering concept designed to optimize the efficacy and ecological sustainability of air *** core objective is to provide highly automated air transportation services for pa...
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Advanced Air Mobility(AAM)has emerged as a pioneering concept designed to optimize the efficacy and ecological sustainability of air *** core objective is to provide highly automated air transportation services for passengers or cargo,operating at low altitudes within urban,suburban,and rural *** seeks to enhance the efficiency and environmental viability of the aviation sector by revolutionizing the way air travel is *** a complex aviation environment,traffic management and control are essential technologies for safe and effective AAM *** of the most difficult obstacles in the envisioned AAM systems is vehicle coordination at merging points and *** escalating demand for air mobility services,particularly within urban areas,poses significant complexities to the execution of such *** this study,we propose a novel multi-agent reinforcement learning(MARL)approach to efficiently manage high-density AAM operations in structured *** approach provides effective guidance to AAM vehicles,ensuring conflict avoidance,mitigating traffic congestion,reducing travel time,and maintaining safe ***,intelligent learning-based algorithms are developed to provide speed guidance for each AAM vehicle,ensuring secure merging into air corridors and safe passage through *** validate the effectiveness of our proposed model,we conduct training and evaluation using BlueSky,an open-source air traffic control simulation *** the simulation of thousands of aircraft and the integration of real-world data,our study demonstrates the promising potential of MARL in enabling safe and efficient AAM *** simulation results validate the efficacy of our approach and its ability to achieve the desired outcomes.
Generative adversarial networks should produce synthetic data that fits the underlying distribution of the data being modeled. For real-valued time series data, this implies the need to simultaneously capture the stat...
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Antimicrobial resistance(AMR)has become a global health crisis in need of novel *** this end,antibiotic combination therapies,which combine multiple antibiotics for treatment,have at-tracted significant attention as a...
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Antimicrobial resistance(AMR)has become a global health crisis in need of novel *** this end,antibiotic combination therapies,which combine multiple antibiotics for treatment,have at-tracted significant attention as a potential approach for combating *** facilitate advances in anti-biotic combination therapies,most notably in investigating antibiotic interactions and identifying synergistic antibiotic combinations however,there remains a need for automated high-throughput plat-forms that can create and examine antibiotic combinations on-demand,at scale,and with minimal reagent *** address these challenges,we have developed a Robotic-Printed Combinatorial Droplet(RoboDrop)platform by integrating a programmable droplet microfuidic device that generates antibiotic combinations in nanoliter droplets in automation,a robotic arm that arranges the droplets in an array,and a camera that images the array of thousands of droplets in *** further implement a resazurin-based bacterial viability assay to accelerate our antibiotic combination *** a demonstration,we use RoboDrop to corroborate two pairs of antibiotics with known interactions and subsequently identify a new synergistic combination of cefsulodin,penicillin,and oxacillin against a model *** *** therefore envision RoboDrop becoming a useful tool to efficiently identify new synergistic antibiotic combinations toward combating AMR.
Endothelial cells are oriented in the direction of blood flow on the inner wall of blood vessels. Endothelial cells are exposed to pulsatile flow and are subjected to periodic wall shear stress. In this study, a devic...
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