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41.
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The paper presents an algebraic construction of the basic notions of soft set theory. Here we introduce the definition of bijective soft groups, dependent and independent soft groups. Some of their properties are investigated. Also we investigate the relationships between bijective soft groups and classical groups. In addition, we express some applications of bijective soft groups on coding theory. 相似文献
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Fault detection, isolation and optimal control have long been applied to industry. These techniques have proven various successful theoretical results and industrial applications. Fault diagnosis is considered as the merge of fault detection (that indicates if there is a fault) and fault isolation (that determines where the fault is), and it has important effects on the operation of complex dynamical systems specific to modern industry applications such as industrial electronics, business management systems, energy, and public sectors. Since the resources are always limited in real-world industrial applications, the solutions to optimally use them under various constraints are of high actuality. In this context, the optimal tuning of linear and nonlinear controllers is a systematic way to meet the performance specifications expressed as optimization problems that target the minimization of integral- or sum-type objective functions, where the tuning parameters of the controllers are the vector variables of the objective functions. The nature-inspired optimization algorithms give efficient solutions to such optimization problems. This paper presents an overview on recent developments in machine learning, data mining and evolving soft computing techniques for fault diagnosis and on nature-inspired optimal control. The generic theory is discussed along with illustrative industrial process applications that include a real liquid level control application, wind turbines and a nonlinear servo system. New research challenges with strong industrial impact are highlighted. 相似文献
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针对深部软岩巷道围岩变形量大,传统支护结构失效的问题,以煤峪口矿回采巷道为研究背景,综合应用数值模拟和工程实践对原支护方案下巷道破坏特征进行分析,提出采用中空注浆锚索进行补强支护,并采用FLAC3D分析了两种支护方案下巷道围岩的收敛量以及应力分布情况,得出了优化支护方案能够有效控制巷道围岩破碎程度,并通过工程实践得到验证。 相似文献
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Giuseppe Schiavone Florian Fallegger Xiaoyang Kang Beatrice Barra Nicolas Vachicouras Evgenia Roussinova Ivan Furfaro Sébastien Jiguet Ismael Seáñez Simon Borgognon Andreas Rowald Qin Li Chuan Qin Erwan Bézard Jocelyne Bloch Grégoire Courtine Marco Capogrosso Stéphanie P. Lacour 《Advanced materials (Deerfield Beach, Fla.)》2020,32(17):1906512
The convergence of materials science, electronics, and biology, namely bioelectronic interfaces, leads novel and precise communication with biological tissue, particularly with the nervous system. However, the translation of lab-based innovation toward clinical use calls for further advances in materials, manufacturing and characterization paradigms, and design rules. Herein, a translational framework engineered to accelerate the deployment of microfabricated interfaces for translational research is proposed and applied to the soft neurotechnology called electronic dura mater, e-dura. Anatomy, implant function, and surgical procedure guide the system design. A high-yield, silicone-on-silicon wafer process is developed to ensure reproducible characteristics of the electrodes. A biomimetic multimodal platform that replicates surgical insertion in an anatomy-based model applies physiological movement, emulates therapeutic use of the electrodes, and enables advanced validation and rapid optimization in vitro of the implants. Functionality of scaled e-dura is confirmed in nonhuman primates, where epidural neuromodulation of the spinal cord activates selective groups of muscles in the upper limbs with unmet precision. Performance stability is controlled over 6 weeks in vivo. The synergistic steps of design, fabrication, and biomimetic in vitro validation and in vivo evaluation in translational animal models are of general applicability and answer needs in multiple bioelectronic designs and medical technologies. 相似文献
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Gilwoon Lee Minsik Kong Doowon Park Junho Park Unyong Jeong 《Advanced materials (Deerfield Beach, Fla.)》2020,32(22):1907477
Although structural coloring and photoluminescence (PL) have been investigated for radiation-responsive color change, electroluminescence (EL) has not been used for the radiation-responsive system. An electro-photoluminescence (EPL) color change is presented here. The phosphors in the alternating current electroluminescence (ACEL) act simultaneously as electro-luminophores and photo-luminophores. The EPL chromaticity is systematically investigated depending on the ACEL frequency and UV intensity. It is found that the PL variation depending on UV intensity is the mechanism of the EPL color change. It is revealed that EL and PL can be controlled independently in the low electric field so that the EPL chromaticity can be adjusted by a linear combination of the EL color and the PL color. The EPL color-changing device is used as a deformable visual encryption system and a soft skin for a soft robotic rover, imitating the concealment and signaling functions in nature. 相似文献
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高压断路器操动机构振动信号为非平稳性信号,蕴含着丰富的操动机构工作状态的信息,对操动机构工作状态的检验辨识具有重大意义。提出一种基于小波时频图和卷积神经网络的断路器故障诊断方法。对操动机构振动信号进行连续小波变换生成时频图(CWT),并对时频图进行统一压缩预处理;将预处理后的时频图作为特征图输入卷积神经网络AlexNet模型;通过对网络参数的调整,逐步改进网络模型,有监督地实现对操动机构故障状态的辨识诊断。结果表明,该方法能够有效地运用于断路器操动机构故障辨识诊断,与小波频带能量-RBF、小波频带能量-SVM的故障识别相比,故障识别准确率最高。 相似文献