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41.
研究采用卫星遥感技术获取高分辨率遥感影像水体样本数据集,基于深度卷积神经网络从高分辨遥感影像中提取水体并进行黑臭水体智能监测,提出了一种改进U-Net的黑臭水体检测网络模型(IWDNet)。基于U-Net结构引入跳跃式多尺度特征融合,结合通道注意力机制、卷积注意力模块、通道与空间注意力机制生成不同多尺度特征融合注意力机制(MFFAM)模块进行对比,并引入空洞卷积扩大网络感受野,最终实现黑臭水体的识别检测。实验证明:基于跳跃式多尺度融合与CBAM注意力机制的黑臭水体检测网络(MFFCBAM-IWNet)模型有效提升了识别精度,在高分辨遥感影像水体样本数据集上表现最佳,总体精度达98.56%,Kappa系数达0.978 4。 相似文献
42.
针对传统的基于稀疏贝叶斯学习(Sparse Bayesian Learning,SBL)的波达方向估计算法对噪声鲁棒性不高的问题,提出了一种基于SBL的子空间拟合离格波达方向(Direction of Arrival,DOA)估计方法。首先对接收数据的协方差矩阵进行特征分解,获得信号的加权子空间,构造等价信号的稀疏表示模型并利用贝叶斯学习算法进行参数求解。同时对于网格划分带来的建模误差问题,采用了离格贝叶斯推导(Sparse Bayesian Inference,SBI)算法进行求解,利用期望最大化算法迭代更新相应的参数。仿真结果表明,相对于传统的DOA方法,该方法具有更好的估计精度。 相似文献
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44.
认知用户通过频谱感知和接入过程识别频谱状态并占用空闲频谱,可有效利用频谱资源。针对频谱感知中存在感知错误和频谱接入中存在用户碰撞的问题,首先建立多用户多信道模型,设计频谱感知和频谱接入过程;然后通过结合双深度Q网络和竞争Q网络,设计竞争双深度Q网络,解决过估计问题的同时优化网络结构;最后通过智能体与所设计模型中状态、观测、回报和策略的交互,完成使用竞争双深度Q网络解决频谱感知和接入问题的一体化研究。仿真结果表明,相比于已有深度强化学习方法,使用竞争双深度Q网络得到的数值结果更稳定且感知正确率和信道利用率都提高了4%。 相似文献
45.
Xingyi Dai Yinghui Wu Qihua Liang Jingkun Yang Long-Biao Huang Jie Kong Jianhua Hao 《Advanced functional materials》2023,33(44):2304415
Flexible sensing technologies that play a pivotal role in endowing robots with detection capabilities and monitoring their motions are impulsively desired for intelligent robotics systems. However, integrating and constructing reliable and sustainable flexible sensors with multifunctionality for robots remains an everlasting challenge. Herein, an entirely intrinsic self-healing, stretchable, and attachable multimodal sensor is developed that can be conformally integrated with soft robots to identify diverse signals. The dynamic bonds cross-linked networks including the insulating polymer and conductive hydrogel with good comprehensive performances are designed to fabricate the sensor with prolonged lifespan and improved reliability. Benefiting from the self-adhesiveness of the hydrogel, strong interfacial bonding can be formed on various surfaces, which promotes the conformable integration of the sensor with robots. Due to the ionic transportation mechanism, the sensor can detect strain and temperature based on piezoresistive and thermoresistive effect, respectively. Moreover, the sensor can work in triboelectric mode to achieve self-powered sensing. Various information can be identified from the electrical signals generated by the sensor, including hand gestures, soft robot crawling motions, a message of code, the temperature of objects, and the type of materials, holding great promise in the fields of environmental detection, wearable devices, human-machine interfacing, and robotics. 相似文献
46.
Xuezhong Zhang Min Wang Yanan Wu Xin Chen Kai Wu Qiang Fu Hua Deng 《Advanced functional materials》2023,33(7):2210027
Moisture–electric generator (MEG)-based blue energy is widely studied. There is still a significant challenge in improving the power of the MEGs system and expanding its application in self-powered electronic skin. Inspired by the structure of ferns, a biomimetic moisture–electric aerogel is designed to collect energy. Polyvinyl alcohol dendritic colloids act as “roots” and “stems” to provide support and channels to transport water molecules. Meanwhile, “leaf-like” graphene oxide sheets generate electricity through direct interaction with water. Besides, based on the above biomimetic structure, this work further enhances the output performance of MEGs by increasing the specific surface area (120.4 m2 g−1) and introducing an ultra-high ion density gradient (from −35 to +37 mV). Meanwhile, due to the excellent water absorption, the MEGs show good salt resistance and cyclic stability. By constructing unique biomimetic structures, ultra-high ion density gradient, and regulating environmental conditions, a high-performance MEG is obtained, including ultra-high open-circuit voltage (1.9 V) and short-circuit current (82.5 µA), the industry-leading power density among MEGs with continuous output is reported in the literature (22.55 µW cm−2). Besides, the MEGs can accurately respond to environmental and pressure changes, showing its application potential in self-powered electronic skin. 相似文献
47.
Zachary Yoder Daniela Macari Gavriel Kleinwaks Ingemar Schmidt Eric Acome Christoph Keplinger 《Advanced functional materials》2023,33(3):2209080
Soft robotic grippers achieve increased versatility and reduced complexity through intelligence embodied in their flexible and conformal structures. The most widely used soft grippers are pneumatically driven; they are simple and effective but require bulky air compressors that limit their application space and external sensors or computationally expensive vision systems for pick verification. In this study, a multi-material architecture for self-sensing electrohydraulic bending actuators is presented that enables a new class of highly versatile and reconfigurable soft grippers that are electrically driven and feature capacitive pick verification and object size detection. These electrohydraulic grippers are fast (step input results in finger closure in 50 ms), draw low power (6.5 mW per finger to hold grasp), and can pick a wide variety of objects with simple binary electrical control. Integrated high-voltage driving electronics are presented that greatly increase the application space of the grippers and make them readily compatible with commercially available robotic arms. 相似文献
48.
Shuang Huang Mengyi He Chuanjie Yao Xinshuo Huang Deyuan Ma Qiqi Huang Jingbo Yang Fanmao Liu Xingqiao Wen Ji Wang Huijiuan Chen Xi Xie 《Advanced functional materials》2023,33(15):2214485
Current catheter devices in minimally invasive surgery still possess limited functional options, lacking multimodal integration of both sensing and therapy. Catheter devices usually operate outside the tissue, incapable to detect intra-tissue biochemical information for accurate localization and assessment of lesions during surgery. Inspired by the feature and functions of Petromyzontidae, here a multimodal core-shell microneedles-integrated bioelectronic catheter (MNIBC) for tissue-penetrating theranostics in endoscopic surgery is developed. The microneedle (MN) device possesses individually addressable functionality at single-MN tip resolution, enabling multiplex functions (a total of 11 functions distributed in three types of catheters) including biochemical sensing, myoelectric modulation, electroporation, and drug delivery in a submucosal environment. The MNIBC is prepared through hybrid fabrication and dimensionality reduction strategies, where the MN electrodes are functionalized with an MXene-carbon nanotube (MXene-CNT)-based electron mediator, addressing the challenge of reduced electrode sensitivity on ultra-small MN tip. The functionalities of MNIBC are demonstrated both ex vivo and in vivo on anesthetized rabbits via laparoscopy, simulated cystoscopy, and laparotomy. The MNIBC can effectively detect intra-tissue biochemical signals in the bladder, and offers localized electroporation and intra-tissue drug delivery for precise treatments of lesions. The versatile features of the MNIBC present a highly advanced platform for precise surgeries. 相似文献
49.
Ultra-Stable and Sensitive Ultraviolet Photodetectors Based on Monocrystalline Perovskite Thin Films
Xu Li Chang Liu Feng Ding Zheyi Lu Peng Gao Ziwei Huang Weiqi Dang Liqiang Zhang Xiaohui Lin Shuimei Ding Bailing Li Ying Huangfu Xiaohua Shen Bo Li Xuming Zou Yuan Liu Lei Liao Yiliu Wang Xidong Duan 《Advanced functional materials》2023,33(15):2213360
The detection of ultraviolet (UV) radiation with effective performance and robust stability is essential to practical applications. Metal halide single-crystal perovskites (ABX3) are promising next-generation materials for UV detection. The device performance of all-inorganic CsPbCl3 photodetectors (PDs) is still limited by inner imperfection of crystals grown in solution. Here wafer-scale single-crystal CsPbCl3 thin films are successfully grown by vapor-phase epitaxy method, and the as-constructed PDs under UV light illumination exhibit an ultralow dark current of 7.18 pA, ultrahigh ON/OFF ratio of ≈5.22 × 105, competitive responsivity of 32.8 A W−1, external quantum efficiency of 10867% and specific detectivity of 4.22 × 1012 Jones. More importantly, they feature superb long-term stability toward moisture and oxygen within twenty-one months, good temperature tolerances at low and high temperatures. The ability of the photodetector arrays for excellent UV light imaging is further demonstrated. 相似文献
50.
Zilong Zhang Wen Zhao Guo Chen Masaya Toda Satoshi Koizumi Yasuo Koide Meiyong Liao 《Advanced functional materials》2023,33(27):2300805
Electrically integrable, high-sensitivity, and high-reliability magnetic sensors are not yet realized at high temperatures (500 °C). In this study, an integrated on-chip single-crystal diamond (SCD) micro-electromechanical system (MEMS) magnetic transducer is demonstrated by coupling SCD with a large magnetostrictive FeGa film. The FeGa film is multifunctionalized to actuate the resonator, self-sense the external magnetic field, and electrically readout the resonance signal. The on-chip SCD MEMS transducer shows a high sensitivity of 3.2 Hz mT−1 from room temperature to 500 °C and a low noise level of 9.45 nT Hz−1/2 up to 300 °C. The minimum fluctuation of the resonance frequency is 1.9 × 10−6 at room temperature and 2.3 × 10−6 at 300 °C. An SCD MEMS resonator array with parallel electric readout is subsequently achieved, thus providing a basis for the development of magnetic image sensors. The present study facilitates the development of highly integrated on-chip MEMS resonator transducers with high performance and high thermal stability. 相似文献