- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Geometric Calibration of Markerless Optical Surgical Navigation System
摘要： Background: Patient-to-image registration is required for image-guided surgical navigation, but marker-based registration is time consuming and subject to manual error. Markerless registration is an alternative solution to avoid these issues. Methods: This study designs a calibration board and proposes a geometric calibration method to calibrate the near infrared tracking and structured light components of the proposed optical surgical navigation system simultaneously. Results: A planar board and a cylinder are used to evaluate the accuracy of calibration. The mean error for the board experiment is 0.035 mm, and the diameter error for the cylinder experiment is 0.119 mm. A calibration board is reconstructed to evaluate the accuracy of the calibration, and the measured mean error is 0.012 mm. A head phantom is reconstructed and tracked by the proposed optical surgical navigation system. The tracking error is less than 0.3 mm. Conclusions: Experimental results show that the proposed method obtains high accessibility and accuracy and satisfies application requirements.
关键词： Calibration,Markerless,Structure light,Optical surgical navigation system
更新于2025-09-23 15:23:52
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Attosecond transient-absorption spectroscopy of polar molecules
摘要： We apply attosecond transient absorption spectroscopy (ATAS) to explore the effects of a nonzero permanent dipole on electron dynamics at the subfemtosecond scale, exemplified in the polar LiF molecule. In contrast with nonpolar systems, a familiar feature of the ATA spectra—the light-induced structures—are observed adjacent to a bright state. Moreover, a previously unobserved ladder structure is identified. The observations are analyzed in the context of a model based on fixed-nuclei adiabatic states, supported by full numerical simulations. Analytic calculations originating in the adiabatic model shed light on the nature and origins of the findings.
关键词： LiF molecule,attosecond transient absorption spectroscopy,electron dynamics,polar molecules,ladder structure,light-induced structures
更新于2025-09-23 15:21:01
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Groove Depth Detection Method Base on the Line Laser Vision Measurement on Cement Concrete Pavement
摘要： The groove depth has a decisive influence on the anti-sliding performance of cement concrete pavement, and it also plays an important role on the noise of cement concrete pavement. Aiming the shortcomings of traditional measurement methods of groove depth detection on the cement concrete pavement, a measurement method base on the structure light vision model was proposed. This method was realized by that the groove depth was obtained by 3D coordinate of the light strip according to the camera model and the structure light plane equation. A new algorithm based on double 2D plane pane target was proposed as the key step of this method.
关键词： groove depth,line laser vision,structure light vision model,cement concrete pavement
更新于2025-09-23 15:19:57
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Plasmonic Ag@TiO <sub/>2</sub> Core-Shell Nanoparticles for Enhanced CO <sub/>2</sub> Photoconversion to CH <sub/>4</sub>
摘要： Ag@TiO2 nanoparticles (NPs) with Ag metal cores and TiO2 semiconductor shells were prepared with a hydrothermal method and their structure was characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The core-shell Ag-TiO2 NPs were deposited on a glass plate and employed as photocatalysts for CO2 conversion by irradiation of solar simulator (AM1.5) under CO2 atmosphere. Selective CH4 evolution by CO2 photoconversion was attained with the core-shell Ag@TiO2 NP photocatalyst. The CH4 evolution rate normalized by specific surface areas was ten times higher than those of reference TiO2 NPs and conventional TiO2 NPs with accompanying Ag deposits. The role of the Ag core was also demonstrated in photodecomposition of a dye by the core-shell Ag@TiO2 NPs. These results suggested the high photocatalytic activity of the core-shell Ag@TiO2 NPs was archived due to bandgap improvement of the TiO2 shell and increase of photon flux to the TiO2 shell by the plasmonic Ag core.
关键词： Photocatalytic CO2 Reduction,Surface Plasmonic Resonance,Ag@TiO2,Core-shell Structure,Light Scattering Effect
更新于2025-09-19 17:13:59
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[IEEE 2018 Australasian Universities Power Engineering Conference (AUPEC) - Auckland, New Zealand (2018.11.27-2018.11.30)] 2018 Australasian Universities Power Engineering Conference (AUPEC) - Nano-structured GaAs Solar Cell Design, Simulation and Analysis for Conversion Efficiency Improvement
摘要： This paper discusses nano-structured GaAs solar cell design and analysis for conversion efficiency improvement by increasing the light transmission and absorption, reducing the light reflection. The focus of this research is to construct different type of nano-grating shaped GaAs solar cells with various nano-grating heights and pitches, to compare the simulation results and find a suitable nano-structure that can provide higher conversion efficiency. Finite difference time domain (FDTD) simulation tool is used to simulate and calculate transmission and absorption for different nano-grating shapes, such as, parabolic, triangular, trapezoidal and rectangular. Based on the simulation results, it has been confirmed that the light reflection of parabolic shaped nano-grating structures is higher than triangular nano-grating structures, but it is lower than rectangular and trapezoidal shaped nano-grating structures. Moreover, the simulation results confirmed that the light transmission of parabolic shaped nano-grating structures is about 62.3% having a 200-nm grating height and an 810-nm grating pitch, which is about 22% higher than the rectangular (i.e., flat) type substrates.
关键词： Finite-difference time-domain method,transmission,GaAs solar cells,and absorption,Nano-grating structure,Light reflection,Conversion efficiency,Solar or renewable energy
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE Eurasia Conference on IOT, Communication and Engineering (ECICE) - Yunlin, Taiwan (2019.10.3-2019.10.6)] 2019 IEEE Eurasia Conference on IOT, Communication and Engineering (ECICE) - Amount and Scattering of Dyes and their Influence on the Photocurrent Enhancement of TiO2 Hierarchically Structured Photoanodes for Dye-Sensitized Solar Cells
摘要： In this study, we prepared and analyzed the properties of hills-like hierarchically structured TiO2 photoanodes for dye-sensitized solar cells (DSSCs). We expected that the presence of appropriately aggregated TiO2 clusters in the photoanode layer would translate in a relatively strong light scattering and dye loading, increasing the photovoltaic efficiency. A detailed light-harvesting study was performed by employing polyvinyl alcohol (PVA) polymers of different molecular weights as binders for the aggregation of the TiO2 nanoparticles (P-25 Degussa). Hence, we obtained a series of TiO2 films presenting a variety of morphologies. Their reflection, as well as the absorbance of the attached dye, the amount of dye loading, and the performance of the fabricated DSSC devices were investigated. Our optimized device presenting a relatively high dye loading and well light harvesting ability, and able to enhance the short-circuit current (Jsc) in the DSSCs by 23%.
关键词： Dye-sensitized solar cell,Hierarchical structure,Light scattering,TiO2 photoanode
更新于2025-09-16 10:30:52
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[IEEE 2019 21st International Conference on Transparent Optical Networks (ICTON) - Angers, France (2019.7.9-2019.7.13)] 2019 21st International Conference on Transparent Optical Networks (ICTON) - Simulations of LED Patterned with IP-DIP Woodpile Structure
摘要： In this paper, we present simulations of three-dimensional (3D) photonic crystal structure (PhC) in IP-Dip polymer. We investigated woodpile structure and LED patterned by woodpile structure by various simulation methods. Structure was designed by the computer aided design (CAD) and optical properties were simulated by finite-difference time-domain (FDTD) and rigorous coupled-wave analyses (RCWA) simulation methods. We are focused on diffraction of optical radiation by woodpile structure and possibility of influencing extraction ratio and radiation patterns of LED with patterned woodpile structure. There is improving a significant percentage of transmittance of the radiation. It results in the influence of the radiation from the LED and it has positive impact on the LED parameters.
关键词： photonic crystal,simulations,3D woodpile structure,light extraction,photonic band gap,radiation pattern
更新于2025-09-11 14:15:04
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An efficient cadmium free inverted red quantum dot light emitting diodes
摘要： Here, we report an efficient inverted red indium phosphide (InP) comprised QD (InP/ZnSe/ZnS, core/shell structure) light-emitting diode (QLED) by modulating an interfacial contact between the electron transport layer and emissive InP-QDs and applying self-aging approach. The red InP-QLED with optimized interfacial contact exhibits a significant improvement in maximum external quantum efficiency and current efficiency from 4.42% to 10.2% and 4.70 cd/A to 10.8 cd/A, respectively, after 69 days of self-aging, which is an almost 2.3-fold improvement compared with the fresh device. The analysis indicates the consecutive reduction in electron injection and accumulation in the emissive QD due to changes in the conduction band minimum of ZnMgO (0.1 eV after 10 days of storage times) through a downward vacuum level shift according to the aging times. During the device aging periods, the oxygen vacancies of ZnMgO reduces, which leads to lower the conductivity of ZnMgO. As a result, the improvement of charge balance in the device with the suppression of exciton quenching at the interface of ZnMgO and InP-QD.
关键词： Cadmium-free quantum dots,charge balance,charge carrier injection layers,inverted structure,light emitting diode
更新于2025-09-11 14:15:04