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91.
92.
为了实现对医疗数据的快速检测和分类识别,需要对医疗数据进行表面重建设计,首先,提出一种基于改进全卷积神经网络的医疗数据表面重建算法.采用无线射频识别技术进行医疗数据的大数据采样,对RFID采集的医疗数据进行信息融合处理,采用多元回归分析方法提取医疗数据的相关性统计特征量,然后,针对医疗数据中的冗余特征采用匹配滤波检测器进行冗余滤波处理,对提纯后的医疗数据采用相空间重构技术实现医疗数据重构,最后,对重构数据采用改进全卷积神经网络分类器进行分类识别,实现医疗数据的表面重建和自动识别.仿真结果表明,所提方法的医疗数据冗余特征处理效果较好,数据分类精度可高达90%以上,且医疗数据重建误差小,耗时少. 相似文献
93.
在人工智能的时代,自动驾驶技术越来越成熟,技术中包含的自动车道保持功能占有重要的地位,这对自动驾驶中的后续车道偏离与预警起着关键性的作用。文章利用深度学习技术,针对现有双分支车道线实例分割检测算法存在的准确率受批量影响、准确率不理想等问题,在车道线实例分割中采用自适配归一化函数,并使用传统的SGD优化器对整个模型进行优化解决实验过程中的效率问题。在TuSimple车道数据集进行实验,在性能方面准确率与原始算法相比从96.4%提高到98.6%。 相似文献
94.
This paper is concerned with robust weighted state fusion estimation problem for a class of time-varying multisensor networked systems with mixed uncertainties including uncertain-variance multiplicative and linearly correlated additive white noises, and packet dropouts. By augmented state method and fictitious noise technique, the original system is converted into one with only uncertain noise variances. According to the minimax robust estimation principle, based on the worst-case system with the conservative upper bounds of uncertain noise variances, four weighted state fusion robust Kalman estimators (filter, predictor and smoother) are presented in a unified form that the robust filter and smoother are designed based on the robust Kalman predictor. Their robustness is proved by the Lyapunov equation approach in the sense that their actual estimation error variances are guaranteed to have the corresponding minimal upper bounds for all admissible uncertainties. Their accuracy relations are proved. The corresponding robust local and fused steady-state Kalman estimators are also presented, and the convergence in a realization between the time-varying and steady-state robust Kalman estimators is proved by the dynamic error system analysis (DESA) method. Finally, a simulation example applied to uninterruptible power system (UPS) shows the correctness and effectiveness of the proposed results. 相似文献
95.
《材料科学技术学报》2019,35(8):1740-1746
Bismuth vanadate (BiVO4) is a promising photoanode material owing to the narrow bandgap, appropriate band position, and excellent resistance against photocorrosion, however, the performance of photoelectrochemical (PEC) water splitting is largely limited by the poor carrier separation and transport ability. To address these issues, for the first time, we fabricate BiVO4 film/CuO nanocone p-n junctions as photoanodes by combing a facile spin-coating process and water bath reaction. This structure strengthens the light harvesting and promotes the charge separation and transport ability. The surface defects states are passivated by coating conformally ultrathin TiO2 onto CuO surface through atomic layer deposition (ALD) technique. Benefiting from the favorable morphology, energy band, and surface treatment, the BiVO4/CuO/TiO2 heterojunction generates an improved photocurrent that is much higher than pure BiVO4. The detailed mechanism investigations indicate that the synergetic optimization of charge separation and injection efficiency in the bulk and surface of photoelectrodes can significantly improve the performance of PEC cells. 相似文献
96.
Lin Li Hongyu Chen Zhimin Fang Xianyi Meng Chuantian Zuo Menglan Lv Yongzhi Tian Ying Fang Zuo Xiao Chongxin Shan Zhengguo Xiao Zhiwen Jin Guozhen Shen Liang Shen Liming Ding 《Advanced materials (Deerfield Beach, Fla.)》2020,32(24):1907257
An electrically modulated single-/dual-color imaging photodetector with fast response speed is developed based on a small molecule (COi8DFIC)/perovskite (CH3NH3PbBr3) hybrid film. Owing to the type-I heterojunction, the device can facilely transform dual-color images to single-color images by applying a small bias voltage. The photodetector exhibits two distinct cut-off wavelengths at ≈544 nm (visible region) and ≈920 nm (near-infrared region), respectively, without any power supply. Its two peak responsivities are 0.16 A W−1 at ≈525 nm and 0.041 A W−1 at ≈860 nm with a fast response speed (≈102 ns). Under 0.6 V bias, the photodetector can operate in a single-color mode with a peak responsivity of 0.09 A W−1 at ≈475 nm, showing a fast response speed (≈102 ns). A physical model based on band energy theory is developed to illustrate the origin of the tunable single-/dual-color photodetection. This work will stimulate new approaches for developing solution-processed multifunctional photodetectors for imaging photodetection in complex circumstances. 相似文献
97.
Yiju Li Shuangyan Lin Dandan Wang Tingting Gao Jianwei Song Peng Zhou Zhikun Xu Zhenghao Yang Ni Xiao Shaojun Guo 《Advanced materials (Deerfield Beach, Fla.)》2020,32(8):1906722
The development of Li–S batteries is largely impeded by the growth of Li dendrites and polysulfide shuttling. To solve these two problems simultaneously, herein the study reports a “single atom array mimic” on ultrathin metal organic framework (MOF) nanosheet-based bifunctional separator for achieving the highly safe and long life Li–S batteries. In the designed separator, the periodically arranged cobalt atoms coordinated with oxygen atoms (Co O4 moieties) exposed on the surface of ultrathin MOF nanosheets, “single atom array mimic”, can greatly homogenize Li ion flux through the strong Li ion adsorption with O atoms at the interface between anode and separator, leading to stable Li striping/plating. Meantime, at the cathode side, the Co single atom array mimic serves as “traps” to suppress polysulfide shuttling by Lewis acid-base interaction. As a result, the Li–S coin cells with the bifunctional separator exhibit a long cycle life with an ultralow capacity decay of 0.07% per cycle over 600 cycles. Even with a high sulfur loading of 7.8 mg cm−2, an areal capacity of 5.0 mAh cm−2 can be remained after 200 cycles. Moreover, the assembled Li–S pouch cell displays stable cycling performance under various bending angles, demonstrating the potential for practical applications. 相似文献
98.
目的探索书法艺术在包装设计中产业化发展现状,分析其未来在包装设计中的主要发展方向及具体的应用策略。方法首先从市场对包装设计的要求切入,分析将书法艺术元素融入包装设计的趋势及作用,然后从实际出发,分析书法艺术在包装设计中的应用现状及其在产业化发展中遇到的现实阻力,再结合图与文、形与意、文化与情感等的应用尝试,总结具体的设计方向,同时以茶叶包装和食品包装设计为例,深入剖析书法艺术在包装设计领域的具体应用,最后从整体视角出发,探索书法艺术在包装设计中产业化发展的有效路径。结论书法艺术有着博大精深、丰富多彩的内涵,将其创新性地融入包装设计中可以赋予包装设计全新的设计视角,有利于丰富包装设计作品的文化底蕴和美学特征,促进包装设计产业化发展。 相似文献
99.
Mingxi Zhang Huan Yu Hang Li Yan Jiang Lihang Qu Yunxia Wang Feng Gao Wei Feng 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(1):2205623
Photoelectrochemical-type visible-blind ultraviolet photodetectors (PEC VBUV PDs) have gained ever-growing attention due to their simple fabrication processes, uncomplicated packaging technology, and high sensitivity. However, it is still challenging to achieve high-performance PEC VBUV PDs based on a single material with good spectral selectivity. Here, it is demonstrated that individual ultrathin indium oxide (In2O3) nanosheets (NSs) are suitable for designing high-performance PEC VBUV PDs with high responsivity and UV/visible rejection ratio for the first time. In2O3 NSs PEC PDs show excellent UV photodetection capability with an ultrahigh photoresponsivity of 172.36 mA W−1 and a high specific detectivity of 4.43 × 1011 Jones under 254 nm irradiation, which originates from the smaller charge transfer resistance (Rct) at the In2O3 NSs/electrolyte interface. The light absorption of In2O3 NSs takes a blueshift due to the quantum confinement effect, granting good spectral selectivity for visible-blind detection. The UV/visible rejection ratio of In2O3 NSs PEC PDs is 1567, which is 30 times higher than that of In2O3 nanoparticles (NPs) and exceeds all recently reported PEC VBUV PDs. Moreover, In2O3 NSs PEC PDs show good stability and good underwater imaging capability. The results verify that ultrathin In2O3 NSs have potential in underwater optoelectronic devices. 相似文献
100.
Dexin Xu Sirui Liu Mingyi Zhang Lingling Xu Hong Gao Jing Yao 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(33):2300201
Surface reconstruction of electrocatalysts is very important to clarify the structure–component–activity relationship. In this work, in situ Raman and ex situ technologies are used to capture the surface structure evolution of F–Fe–CoP during the oxygen evolution reaction (OER). The results reveal that the leaching of F accelerates the dynamic reconstruction response of CoP to rapidly convert into active (oxy)hydroxide species. The further introduction of Fe can accelerate the charge transfer rate and alleviate the structural stacking caused by insufficient kinetics. The introduction of F and Fe increases the electron occupation states of cobalt sites and promotes the adsorption of OH− ions on the CoP catalyst, which significantly improves the OER performance. F–Fe–CoP exhibits excellent OER performance with an overpotential of 259 mV at 20 mA cm−2. This finding enriches the OER mechanism associated with the surface reconstruction of CoP and provides a reference for the rational design of efficient electrocatalysts. 相似文献