Passive daytime radiative cooling is of tremendous interest but would be overcooling during cold nights or winter days, exacerbating the heating cost, especially in high-latitude areas. Integrating the heating and coo...
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Simultaneous ideal quantum measurements of multiple single-photon-level signals would advance applications in quantum information processing, metrology, and astronomy but require the first amplifier to be simultaneous...
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Simultaneous ideal quantum measurements of multiple single-photon-level signals would advance applications in quantum information processing, metrology, and astronomy but require the first amplifier to be simultaneously broadband, quantum limited, and directional. However, conventional traveling-wave parametric amplifiers support broadband amplification at the cost of increased added noise and are not genuinely directional due to non-negligible nonlinear backward-wave generation. In this work, we introduce a new class of amplifiers that encode the information in the Floquet modes of the system. Such Floquet-mode amplifiers prevent information leakage and overcome the trade-off between quantum efficiency (QE) and bandwidth. Crucially, Floquet-mode amplifiers strongly suppress the nonlinear forward-backward wave coupling and are therefore genuinely directional and readily integrable with qubits, clearing another major obstacle toward broadband ideal quantum measurements. Furthermore, Floquet-mode amplifiers are insensitive to out-of-band impedance mismatch, which otherwise may lead to gain ripples, parametric oscillations, and instability in conventional traveling-wave parametric amplifiers. Finally, we show that a Floquet-mode Josephson traveling-wave parametric amplifier implementation can simultaneously achieve >20dB gain and a QE of η/ηideal>99.9% of the quantum limit over more than an octave of bandwidth. The proposed Floquet scheme is also widely applicable to other platforms, such as kinetic inductance traveling-wave amplifiers and optical parametric amplifiers.
We employ the physics of chiral bound state in the continuum and suggest planar chiral metasurfaces with near-perfect circular dichroism (CD). We demonstrate experimentally metasurfaces with CD=0.9 with Q factor excee...
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No-reference image quality assessment (NR-IQA) aims to quantify how humans perceive visual distortions of digital images without access to their undistorted references. NR-IQA models are extensively studied in computa...
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The interaction between an atom and an electromagnetic mode of a resonator is of both fundamental interest and is ubiquitous in quantum technologies. Most prior work studies a linear light-matter coupling of the form ...
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This paper studies the problem of secure state estimation of a linear time-invariant (LTI) system with bounded noise in the presence of sparse attacks on an unknown, time-varying set of sensors. At each time, the atta...
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This paper studies the problem of secure state estimation of a linear time-invariant (LTI) system with bounded noise in the presence of sparse attacks on an unknown, time-varying set of sensors. At each time, the attacker has the freedom to choose an arbitrary set of no more than p sensors and manipulate their measurements without restraint. To this end, we propose a secure state estimation scheme and guarantee a bounded estimation error irrespective of the attack signals subject to 2p-sparse observability and a mild, technical assumption that the system matrix has no degenerate eigenvalues. The proposed scheme comprises a design of decentralized observers for each sensor based on the local observable subspace decomposition. At each time step, the local estimates of sensors are fused by a median operator to obtain a secure estimation, which is then followed by a local detection-and-resetting process of the decentralized observers. The estimation error is shown to be upper-bounded by a constant which is determined only by the system parameters and noise magnitudes. Moreover, we design the detector threshold to ensure that the benign sensors never trigger the detector. The efficacy of the proposed algorithm is demonstrated by its application on a benchmark example of IEEE 14-bus system. We show that our proposed scheme can effectively tolerate sparse attacks on an unknown set of sensors, ensuring a bounded estimation error and effectively detecting and resetting the attacked sensors.
We consider a perimeter defense problem in a planar conical environment in which a single vehicle, having a finite capture radius, aims to defend a concentric perimeter from mobile intruders. The intruders are arbitra...
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Improving operational efficiency and lowering environmental impact are made possible by optimizing energy usage in industrial cooling tower systems. This paper presents a new method for optimizing the management of in...
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ISBN:
(数字)9798350376425
ISBN:
(纸本)9798350376432
Improving operational efficiency and lowering environmental impact are made possible by optimizing energy usage in industrial cooling tower systems. This paper presents a new method for optimizing the management of industrial cooling towers, with a particular emphasis on energy savings, by combining Internet of Things (IoT) technologies with Gradient Boosting approaches. IoT sensors monitor the cooling system’s temperature, flow rate, and humidity in real time. This data makes predictive analytics on system performance and energy usage possible by training Gradient Boosting models. It shows that the proposed approach successfully achieves substantial energy savings while keeping cooling tower performance at its optimum via extensive testing and analysis. The findings show that Gradient Boosting and IoT monitoring might help industrial settings with proactive energy management. By providing a workable framework for improving cooling tower operations' energy efficiency of sustainable industrial practices. The results highlight the significance of using data-driven strategies and advanced technology to solve energy problems in manufacturing, which will enhance efficiency and sustainability while reducing costs. Data analysis from the real world, performance measurements, and comparison findings show that the system is more efficient and system performance of assessment.
This work presents the conception and design of log-periodic nano-antenna for the infrared IR solar energy harvesting applications. The suggested nano-antenna contain three layers. The first layer contains two arms of...
This work presents the conception and design of log-periodic nano-antenna for the infrared IR solar energy harvesting applications. The suggested nano-antenna contain three layers. The first layer contains two arms of the log-periodic nano-antenna made of gold (Au), the second is a quartz substrate and finally, the ground layer is a gold (Au) plane reflector. The analysis of the proposed nano-antenna is performed using FDTD technique in the range of frequencies [28 to 29 THz]. A huge parametric study was performed to optimize the different parameters (thickness of the arms, teeth angle, number of teeth, substrate thickness, solid angles, and inner radius) of the nano-antenna. With the optimized design parameters, the structure captures a maximum electric field E at the hotspot point of around 800 V/m. The optimized geometry and shape of the presented structure make it a suitable choice to design a metal-insulator-metal (MIM) rectifier system in order to harvest solar infrared IR energy with good performance in terms of E-field, current-voltage I/V, resistance, and responsivity.
This paper investigates the optimal landing trajectory and control procedure when a helicopter undergoes autorotation due to tail rotor drive failure (TRDF), in which an optimal control methodology is proposed. First,...
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