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- 摘要
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- 实验方案
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[IEEE 2018 Conference on Optoelectronic and Microelectronic Materials and Devices (COMMAD) - Perth, Australia (2018.12.9-2018.12.13)] 2018 Conference on Optoelectronic and Microelectronic Materials and Devices (COMMAD) - A new approach to modelling the coherence of optical feedback in dynamical semiconductor laser systems
摘要： This paper proposes a model-based range extension control system for electric vehicles. The proposed system optimizes the front and rear driving–braking force distributions by considering the slip ratio of the wheels and the motor loss. The optimal distribution depends solely on vehicle acceleration and velocity. Therefore, this system is effective not only at constant speeds but also in acceleration and deceleration modes. Bench tests were conducted for more precise evaluation and to realize experimental results with high reproducibility. The effectiveness of the proposed system was verified through field and bench tests.
关键词： Bench test,range extension control system (RECS),electric vehicle (EV),driving and braking force distribution
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE Intelligent Transportation Systems Conference - ITSC - Auckland, New Zealand (2019.10.27-2019.10.30)] 2019 IEEE Intelligent Transportation Systems Conference (ITSC) - Training a Fast Object Detector for LiDAR Range Images Using Labeled Data from Sensors with Higher Resolution
摘要： In this paper, we describe a strategy for training neural networks for object detection in range images obtained from one type of LiDAR sensor using labeled data from a different type of LiDAR sensor. Additionally, an efficient model for object detection in range images for use in self-driving cars is presented. Currently, the highest performing algorithms for object detection from LiDAR measurements are based on neural networks. Training these networks using supervised learning requires large annotated datasets. Therefore, most research using neural networks for object detection from LiDAR point clouds is conducted on a very small number of publicly available datasets. Consequently, only a small number of sensor types are used. We use an existing annotated dataset to train a neural network that can be used with a LiDAR sensor that has a lower resolution than the one used for recording the annotated dataset. This is done by simulating data from the lower resolution LiDAR sensor based on the higher resolution dataset. Furthermore, improvements to models that use LiDAR range images for object detection are presented. The results are validated using both simulated sensor data and data from an actual lower resolution sensor mounted to a research vehicle. It is shown that the model can detect objects from 360? range images in real time.
关键词： self-driving cars,object detection,LiDAR,range images,neural networks
更新于2025-09-19 17:13:59
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Automotive 3.0 ?μm Pixel High Dynamic Range Sensor with LED Flicker Mitigation
摘要： We present and discuss parameters of a high dynamic range (HDR) image sensor with LED flicker mitigation (LFM) operating in automotive temperature range. The total SNR (SNR including dark fixed pattern noise), of the sensor is degraded by floating diffusion (FD) dark current (DC) and dark signal non-uniformity (DSNU). We present results of FD DC and DSNU reduction, to provide required SNR versus signal level at temperatures up to 120°C. Additionally we discuss temperature dependencies of quantum efficiency (QE), sensitivity, color effects, and other pixel parameters for backside illuminated image sensors. Comparing +120°C junction vs. room temperature, in visual range we measured a few relative percent increase, while in 940 nm band range we measured 1.46x increase in sensitivity. Measured change of sensitivity for visual bands—such as blue, green, and red colors—reflected some impact to captured image color accuracy that created slight image color tint at high temperature. The tint is, however, hard to detect visually and may be removed by auto white balancing and temperature adjusted color correction matrixes.
关键词： temperature dependence,sensitivity,LED flicker mitigation,quantum efficiency,automotive,CMOS,high dynamic range,image sensor
更新于2025-09-19 17:13:59
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Rapid and wide-range detection of NO <sub/>x</sub> gas by N-hyperdoped silicon with the assistance of a photovoltaic self-powered sensing mode
摘要： Wide dynamic range NOx sensors are vital for environment and health purposes, but few sensors could achieve wide range detection with ultralow and ultrahigh concentrations at the same time. In this article, the microstructured and nitrogen-hyperdoped silicon (N-Si) for NOx gas sensing is investigated systematically. Working by the change of surface conductivity, the sensor is ultra-sensitive to low concentration of NOx down to 11 ppb, and shows a rapid response/recovery time of 22/33 s for 80 ppb. When NOx concentration increases and exceeds a threshold value (10–50 ppm), an n–p conduction type transition is observed due to the inversion of the conduction type of major carriers, which limits the sensor’s dynamic range at high concentration. However, when the sensor works in a photovoltaic self-powered mode under the asymmetric light illumination (ALI), the limitation can be successfully overcome. Therefore, with the combination of the two working principles, a wide dynamic range stretching over six orders of magnitude (~0.011–4,000 ppm) can be achieved.
关键词： dynamic range,conduction type transition,asymmetric light illumination,hyperdoped silicon,self-powered gas sensing
更新于2025-09-19 17:13:59
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Industrial Applications of Nanomaterials || Nanomaterials-based UV photodetectors
摘要： Photodetectors are essential elements applied in video imaging, optical communications, biomedical imaging, security, night-vision, gas sensing, and motion detection, which possess the ability to transform light into electrical signals precisely. As the scale and diversity of application areas are growing, the need for innovative photodetection platform technologies with higher performance in terms of speed, efficiency or wavelength range, as well as material flexibility, transparency, and complementary metal-oxide-semiconductor (CMOS) integrability, is becoming more critical. In the past decades, extensive efforts have been devoted to explore the next generation of photodetector materials, such as In2Te3, ZnO, and GaN, with low noise, high photosensitivity, and good stability. However, many of these novel photodetector materials still suffer from limited photocurrent and photoresponse speed.
关键词： Nanomaterials,Schottky contacts,photoconductive gain,photodetection mechanism,photoresistors,linear dynamic range,responsivity,external quantum efficiency,photodiodes,specific detectivity,UV photodetectors
更新于2025-09-19 17:13:59
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Temperature-controlled synthesis of hollow, porous gold nanoparticles with wide range light absorption
摘要： An easy synthesis method of hollow, porous gold nanoparticles (AuHP NPs) with controlled diameter and pores sizes and with a wide range of light absorbance (continuous between 500 and 900 nm) is presented together with the explanation of the nanoparticle formation mechanism. The NPs were investigated using transmission electron microscopy (TEM) combined with the selected area electron diffraction patterns, X-ray diffraction and ultraviolet–visible spectroscopy. TEM images showed that changing the synthesis temperature allows to obtain AuHP NPs with sizes from 35 ± 4 nm at 60 °C to 76 ± 8 nm at 90 °C. The effects of nanoscale porosity on the far- and near-field optical properties of the nanoparticles, as well as on effective conversion of electromagnetic energy into thermal energy, were applied in simulated photothermal cancer therapy. The latter one was simulated by irradiation of two cancer cell lines SW480 and SW620 with lasers operating at 650 nm and 808 nm wavelengths. The mortality of cells after using the synthesized AuHP NPs as photosensitizers is between 20 and 50% and increases with the decrease in the diameter of the AuHP NPs. All these attractive properties of the AuHP NPs make them find application in many biomedical studies.
关键词： photothermal therapy,wide range light absorption,temperature-controlled synthesis,hollow porous gold nanoparticles
更新于2025-09-19 17:13:59
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Measurement of Electromagnetic Characteristics Materials in a Rectangular Waveguide
摘要： A waveguide method for measuring the relative complex dielectric constant of ?at samples of insulating materials that is invariant to the position of the sample over a waveguide section is discussed. The exclusion of the e?ect of coaxial-waveguide transitions on the measurement results is performed by the LR method. The measured parameters are determined in the frequency range by minimizing the objective function.
关键词： frequency range,LR method,waveguide method,complex dielectric constant,insulating materials
更新于2025-09-19 17:13:59
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Experimental Methods for Studying the Power Contrast of Laser Radiation
摘要： The streak-camera method for measuring the laser radiation (LR) front pro?le with a large dynamic range and the method for measuring the power contrast based on photodiodes are described. The results of the implementation of these measurement methods at the “Luch” facility of the RFNC–VNIIEF using the SER-5 streak camera developed by the authors and specially developed optical schemes are presented. The results of measurements of the LR power contrast, performed in power experiments and demonstrating the possibility of measuring deep pro?les of pulses with a dynamic range to 106 and 109 and a time resolution of 250 ps and 70 ps (at the ?rst and second harmonics, respectively) are presented.
关键词： dynamic range,streak camera,power contrast
更新于2025-09-19 17:13:59
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A calibration method of dual two-dimensional laser range finders for mobile manipulator
摘要： In this article, a method for calibrating the relative position between dual two-dimensional laser range finders is proposed. This relative position is affected by the manufacture or assembling error of mobile platform, and this error could reduce the accuracy of localization. This article focuses on three-degree-of-freedom calibration, that is, one rotational and two translational degrees of freedom. The entire calibration process can be summed up into three steps. The first step is to allow the dual finders to scan one corner at the same time and then extract the parameters of the corner. The second step is to establish a cost function which is established according to the direction vector of the line and the repeatability of the corners. With this function, the genetic algorithm is used to obtain the final calibration result. Moreover, the finder systematic error and the statistical error are also considered into this article. Simulations and experiments are carried out to verify the proposed method.
关键词： 2-D laser range finder,genetic algorithm,Calibration,mobile manipulator
更新于2025-09-19 17:13:59
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Surface Polariton‐Like s‐Polarized Waveguide Modes in Switchable Dielectric Thin Films on Polar Crystals
摘要： Surface phonon polaritons (SPhPs) and surface plasmon polaritons (SPPs), evanescent modes supported by media with negative permittivity, are a fundamental building block of nanophotonics. These modes are unmatched in terms of field enhancement and spatial confinement, and dynamical all-optical control can be achieved, e.g., by employing phase-change materials. However, the excitation of surface polaritons in planar structures is intrinsically limited to p-polarization. On the contrary, waveguide modes in high-permittivity films can couple to both p- and s-polarized light, and in thin films, their confinement can become comparable to surface polaritons. Here, it is demonstrated that the s-polarized waveguide mode in a thin Ge3Sb2Te6 (GST) film features a similar dispersion, confinement, and electric field enhancement as the SPhP mode of the silicon carbide (SiC) substrate, while even expanding the allowed frequency range. Moreover, it is experimentally shown that switching the GST film grants nonvolatile control over the SPhP and the waveguide mode dispersions. An analytical model is provided for the description of the GST/SiC waveguide mode and it is shown that the concept is applicable to the broad variety of polar crystals throughout the infrared spectral range. As such, complementarily to the polarization-limited surface polaritons, the s-polarized waveguide mode constitutes a promising additional building block for nanophotonic applications.
关键词： waveguide modes,infrared spectral range,phase-change materials,surface plasmon polaritons,silicon carbide,nanophotonics,Ge3Sb2Te6,surface phonon polaritons,s-polarized light
更新于2025-09-19 17:13:59