- 标题
- 摘要
- 关键词
- 实验方案
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Universal Spectral Features of Ultrastrongly Coupled Systems
摘要： We identify universal properties of the low-energy subspace of a wide class of quantum optical models in the ultrastrong coupling limit, where the coupling strength dominates over all other energy scales in the system. We show that the symmetry of the light-matter interaction is at the origin of a twofold degeneracy in the spectrum. We prove analytically this result for bounded Hamiltonians and extend it to a class of models with unbounded operators. As a consequence, we show that the emergence of superradiant phases previously investigated in the context of critical phenomena, is a general property of the ultrastrong coupling limit. The set of models we consider encompasses different scenarios of possible interplay between critical behavior and superradiance.
关键词： superradiant phases,ultrastrong coupling,critical phenomena,quantum optical models
更新于2025-09-19 17:13:59
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Parameters identification of photovoltaic cells and modules using diversification-enriched Harris hawks optimization with chaotic drifts
摘要： In this research, a diversification-enhanced Harris hawks optimization (HHO) is proposed based on the chaotic drifts in the vicinity of the best agent and an opposition-based exploratory strategy to efficiently identify unknown parameters of photovoltaic models modules. This novel technique is employed to estimate the parameters of solar cells models for single diode, double diode, and photovoltaic module. Also, different temperatures and irradiation levels for three practical manufactures datasets are investigated. Competitive and statistical experimental results demonstrate the excellent traits of the proposed HHO-based identifier in estimating the key parameters of photovoltaic models compared to several well-regarded competitors that prominently performs a good performance for solving this case. Also, satisfactory stability level is archived at different temperatures and levels of irradiance due to a better interchange between diversification and intensification drifts of the proposed variant. Therefore, HHO-based identifier provides high-quality solutions for parameter identification cases based on its coherent searching trends. We recommend this approach as a competent and auxiliary technique for parameters estimation of photovoltaic models.
关键词： Swarm-intelligence,Exploration and exploitation,Photovoltaic models,Parameters estimation,Harris Hawks Optimization
更新于2025-09-19 17:13:59
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Quantum collapse as reduction from a continuum of conditional amplitudes in an entangled state to a single actualized amplitude in the collapsed state
摘要： According to the Copenhagen interpretation of quantum mechanics a measurement leads to the collapse of a quantum system. A uni?ed description of a quantum system before and after measurement of the position ra1 and the spin sa1 of one of its electrons is proposed based on the conditional amplitude and its density. Quantum collapse is described as reduction from continuum of the conditional amplitudes {(cid:2)(x2, . . . , xN |rh1 )} in an initial quantum state to the single actualized amplitude (cid:2)(x2, . . . , xN |ra1 ) in a collapsed state. The latter state contains the information about quantum entanglement, the extraction of which with fragment entanglement measure is demonstrated for the realistic valence bond models of the dissociating dihydrogen and ethylene molecules.
关键词： ethylene molecules,quantum collapse,dihydrogen,conditional amplitude,quantum entanglement,valence bond models
更新于2025-09-19 17:13:59
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Online Milk Quality Assessment during Milking Using Near-infrared Spectroscopic Sensing System
摘要： In recent times, there has been an urgent requirement for a technique that can be used by dairy farmers to assess the quality of milk of an individual cow during milking. A near-infrared (NIR) spectroscopic sensing system was designed on an experimental basis for the online assessment of the three major milk constituents (fat, protein, and lactose), solids not fat (SNF), milk urea nitrogen (MUN), and somatic cell count (SCC). This system was used to obtain the NIR spectra of non-homogenized milk during milking over a wavelength range of 700 to 1,050 nm. Calibration models for predicting three major milk constituents, SNF, MUN and SCC of non-homogenized milk were developed, and the precision and accuracy of the models were validated. The coefficients of determination, standard errors of prediction, and bias values showed high levels of precision and accuracy for the prediction of the considered parameters. The results indicated that the developed NIR spectroscopic sensing system can be used to assess milk quality in real-time during milking. This system can provide dairy farmers with information concerning milk quality and physiological condition of each cow, and can therefore optimize dairy farm management.
关键词： calibration models,milk constituents,somatic cell count,solids not fat,milk urea nitrogen
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Combinatorial study of MZO emitters for CdTe-based solar cells
摘要： Loneliness is a common condition in older adults and is associated with increased morbidity and mortality, decreased sleep quality, and increased risk of cognitive decline. Assessing loneliness in older adults is challenging due to the negative desirability biases associated with being lonely. Thus, it is necessary to develop more objective techniques to assess loneliness in older adults. In this paper, we describe a system to measure loneliness by assessing in-home behavior using wireless motion and contact sensors, phone monitors, and computer software as well as algorithms developed to assess key behaviors of interest. We then present results showing the accuracy of the system in detecting loneliness in a longitudinal study of 16 older adults who agreed to have the sensor platform installed in their own homes for up to 8 months. We show that loneliness is significantly associated with both time out-of-home (β = ?0.88 and p < 0.01) and number of computer sessions (β = 0.78 and p < 0.05). R2 for the model was 0.35. We also show the model’s ability to predict out-of-sample loneliness, demonstrating that the correlation between true loneliness and predicted out-of-sample loneliness is 0.48. When compared with the University of California at Los Angeles loneliness score, the normalized mean absolute error of the predicted loneliness scores was 0.81 and the normalized root mean squared error was 0.91. These results represent first steps toward an unobtrusive, objective method for the prediction of loneliness among older adults, and mark the first time multiple objective behavioral measures that have been related to this key health outcome.
关键词： longitudinal models,loneliness,In-home monitoring,ambient assessment,older adults
更新于2025-09-19 17:13:59
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Single-Layer Mode Composite Coplanar Waveguide Dual-Band Filter With Large Frequency Ratio
摘要： Grasping and manipulating everyday objects in a goal-directed manner is an important ability of a service robot. The robot needs to reason about task requirements and ground these in the sensorimotor information. Grasping and interaction with objects are challenging in real-world scenarios, where sensorimotor uncertainty is prevalent. This paper presents a probabilistic framework for the representation and modeling of robot-grasping tasks. The framework consists of Gaussian mixture models for generic data discretization, and discrete Bayesian networks for encoding the probabilistic relations among various task-relevant variables, including object and action features as well as task constraints. We evaluate the framework using a grasp database generated in a simulated environment including a human and two robot hand models. The generative modeling approach allows the prediction of grasping tasks given uncertain sensory data, as well as object and grasp selection in a task-oriented manner. Furthermore, the graphical model framework provides insights into dependencies between variables and features relevant for object grasping.
关键词： learning and adaptive systems,recognition,probabilistic graphical models,grasping,Cognitive human–robot interaction
更新于2025-09-19 17:13:59
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Comparative study on parameter extraction of photovoltaic models via differential evolution
摘要： Parameter extraction of photovoltaic (PV) models, which remains a multi-variable, nonlinear, and multi-modal problem, has recently gained considerable attention in the simulation and calculation of solar PV systems. Among various parameter extraction techniques, differential evolution (DE) and its variants are envisaged to be pretty effective for parameter extraction of PV models. In this paper, 11 state-of-the-art DE algorithms are comprehensively compared to extract the parameters of different PV models. The performance of each algorithm is evaluated based on the accuracy of solution, convergence speed, and the robustness. Based on the experimental results and analysis of different DE algorithms, the useful insights are concluded, which can guide the improvement of designing more efficient alternative DE methods for solving the PV parameter extraction problems.
关键词： Comparative study,Parameter extraction,Differential evolution,Photovoltaic models
更新于2025-09-19 17:13:59
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Evaluation of Solar Radiation Transposition Models for Passive Energy Management and Building Integrated Photovoltaics
摘要： Incident solar radiation modelling has become of vital importance not only in architectural design considerations, but also in the estimation of the energy production of photovoltaic systems. This is particularly true in the case of buildings with integrated photovoltaics (PV) systems having a wide range of orientations and inclinations defined by the skin of the building. Since solar radiation data at the plane of interest is hardly ever available, this study presents the analysis of two of the most representative transposition models used to obtain the in-plane irradiance using as input data the global and diffuse irradiation on the horizontal plane, which can be obtained by satellite-based models or ground measurements. Both transposition models are validated with experimental measurements taken in Murcia (southeast of Spain) and datasets provided by the photovoltaic geographical information system (PVGIS) and the National Renewable Energy Laboratory (NREL) for vertical surfaces facing the four cardinal points. For the validation, the mean bias deviation, root mean square error and forecasted skill were used as indicators. Results show that the error rate decreases slightly for clear days. Better results are also obtained by dismissing data with low solar elevation angles so as to avoid shadowing effects from the surroundings in the early and late hours of the day, which affects mainly the performance of the transposition models for west and east surfaces. The results highlight the potential of equator-facing fa?ades in winter time when the received irradiation can be twice as much as the one collected by the horizontal plane. It is also noteworthy that the operating conditions of all fa?ades are mainly low irradiance and medium temperature at these locations.
关键词： PV fa?ades,BIPV,anisotropic sky models,solar irradiance
更新于2025-09-19 17:13:59
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Rationality Modeling of 3D Scanning Image of Digital Print Laser Based on Block Matching Texture Information Repair
摘要： We experimentally investigate mutual information and generalized mutual information for coherent optical transmission systems. The impact of the assumed channel distribution on the achievable rate is investigated for distributions in up to four dimensions. Single channel and wavelength-division multiplexing (WDM) transmission over transmission links with and without inline dispersion compensation are studied. We show that for conventional WDM systems without inline dispersion compensation, a circularly symmetric complex Gaussian distribution is a good approximation of the channel. For other channels, such as with inline dispersion compensation, this is no longer true and gains in the achievable information rate are obtained by considering more sophisticated four-dimensional (4D) distributions. We also show that for nonlinear channels, gains in the achievable information rate can also be achieved by estimating the mean values of the received constellation in four dimensions. The highest gain for such channels is seen for a 4D correlated Gaussian distribution.
关键词： mutual Information,digital communication,fiber nonlinear optics,optical fiber communication,Channel models
更新于2025-09-19 17:13:59
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Composition, structure and morphology of ZnOa??Co3O4 ceramic targets in the process of pulsed laser thin film deposition
摘要： This paper presents the results of the study of the composition, structure and morphology of ZnO–Co3O4 ceramic targets before and after laser ablation by the KrF excimer laser. X-ray diffraction analysis showed that the composition of the targets changes under the thermal effects of laser radiation: a new phase of CoO of the cubic structure is formed (a = 4.25 ?). The radial distribution of elements in the ZnO–Co3O4 targets after ablation by the KrF excimer laser was discovered for the first time. The atomic concentration of cobalt in the center was determined to be several times higher than its concentration at the edge of the targets. This can be explained by the thermal model of laser-semiconductor interaction. The morphology of the targets surface after the laser ablation was discovered to undergo significant changes. Pulsed nanosecond laser radiation induces the formation of center-oriented cone-shaped structures and micro-whiskers on the target surface. It was determined that the higher is the concentration of doping impurities in the target, the greater is the number of structures observed on the surface. The formation of “cones” and microwhiskers is explained by the generalized growth model of the vapor–liquid–crystal mechanism.
关键词： A1. Growth models,A2. Bulk crystal growth,A1. Characterization,A3. Physical vapor deposition processes,B2. Semiconducting II-VI materials,A1. Crystal structure
更新于2025-09-19 17:13:59