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2.
Xiehuan Li Dan Ye 《International Journal of Adaptive Control and Signal Processing》2022,36(1):104-121
In this article, the memory-based dynamic event-triggered controller design issue is investigated for networked interval type-2 (IT2) fuzzy systems under non-periodic denial-of-service (DoS) attacks. For saving limited network bandwidth, a novel memory-based dynamic event-triggered mechanism (DETM) is proposed to schedule data communication. Unlike existing event-triggered generators, the developed memory-based DETM can utilize a series of newly released signals and further save network resources by introducing interval dynamic variables. Moreover, to improve design flexibility, an IT2 fuzzy controller with freely selectable fuzzy rule number and premise membership functions (MFs) is synthesized. Then, a new switched time-delay system with imperfectly matched MFs is established under the consideration of memory-based DETM and DoS attacks simultaneously. Besides, based on the property of MFs, the boundary information of membership grades and slack matrices are introduced in the stability analysis. Furthermore, by using a piecewise Lyapunov–Krasovskii method, membership-functions-dependent criteria are deduced to ensure the asymptotic stability of built fuzzy switched systems. Finally, the effectiveness of proposed control strategies is demonstrated by simulation examples. 相似文献
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Telecommunication Systems - Machine to Machine technology has a broad application prospect in the 5G network, but there is a bottleneck in the energy consumption of intelligent devices powered by... 相似文献
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近年来,随着全球气候变暖和对能源安全方面的考量,氢能产业在全球范围内升温,美国、日本、欧盟等发达国家及地区相继制定了氢能发展战略及规划,日本在全球氢能产业发展中表现突出,国家政策导向明确,氢能产业已成体系.我国已将氢能开发利用作为能源技术发展的重要战略方向,将"推动充电、加氢等设施建设"首次写入2019年《政府工作报告》,石化企业在国家及各级地方政府政策和规划的激励下,积极开展氢能开发利用研究.能源转型是一个漫长的过程,氢能在制取、储存运输以及利用方面还存在碳排放、安全、成本等技术障碍.建议石化企业要保持环保初心、利用自身优势,绿色开展化石能源制氢及利用. 相似文献
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Dr. Jie Zang Dr. Fei Ye Dr. Sara M. Ø. Solbak Dr. Lars J. Høj Prof. Mingjie Zhang Prof. Anders Bach 《ChemMedChem》2021,16(6):949-954
Inhibition of PSD-95 has emerged as a promising strategy for the treatment of ischemic stroke, as shown with peptide-based compounds that target the PDZ domains of PSD-95. In contrast, developing potent and drug-like small molecules against the PSD-95 PDZ domains has so far been unsuccessful. Here, we explore the druggability of the PSD-95 PDZ1-2 domain and use fragment screening to investigate if this protein is prone to binding small molecules. We screened 2500 fragments by fluorescence polarization (FP) and validated the hits by surface plasmon resonance (SPR), including an inhibition counter-test, and found four promising fragments. Three ligand efficient fragments were shown by 1H,15N HSQC NMR to bind in the small hydrophobic P0 pockets of PDZ1-2, and one of them underwent structure-activity relationship (SAR) studies. Overall, we demonstrate that fragment screening can successfully be applied to PDZ1-2 of PSD-95 and disclose novel fragments that can serve as starting points for optimization towards small-molecule PDZ domain inhibitors. 相似文献
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Kai Han Xin‐Yang Li Ye‐Qi Zhang Yong‐Lin He Rui Hu Xiu‐Li Lu Qi‐Jiu Li Jing Hui 《European Journal of Lipid Science and Technology》2020,122(4)
Hyperlipidemia is a common cardiovascular disease. At present, the influence of high fat diet (HFD) on this is being explored. Recently, vegetable oils rich in omega‐3 have been reported that can treat hyperlipidemia caused by HFD. However, the effects of chia seed oil (CSO) on HFD‐induced hyperlipidemia and oxidative stress are poorly studied. Hence, in this study, the effects of CSO on hyperlipidemia and oxidative stress induced by HFD in mice are analyzed by various commercial kits, section staining, and protein expression. The results show that CSO decreases body weight and organ index. Meanwhile, CSO reduces serum lipid levels of total cholesterol, triglyceride, and low‐density lipoprotein cholesterol. It can also elevate superoxide dismutase and glutathione peroxidase activities and reduce malondialdehyde content in serum and liver. The results of histopathological analysis prove that CSO improves hepatic steatosis and reduces lipid deposition. Further, the results of western blot demonstrate that CSO upregulates the expression of peroxisome proliferator‐activated receptor alpha and carnitine palmitoyltransferase 1a in the liver. As a result, CSO may be a potential lipid‐lowering oil to prevent and treat HFD‐induced hyperlipidemia and oxidative stress. Practical Applications CSO, as a byproduct of chia seed processing, is a rich source of α‐linolenic acid. This study investigates the effects of CSO on HFD‐induced hyperlipidemia and oxidative stress in mice. It is concluded that dietary CSO can improve the hyperlipidemia in HFD‐induced mice via analysis of lipid parameters, histopathology study of the liver, and lipid metabolism related genes. In addition, supplementation of CSO also can improve the oxidative stress in mice. Therefore, CSO can be used for the prevention of hyperlipidemia and oxidative stress. This research provides a theoretical basis for the comprehensive development and utilization of functional chia seed oil. 相似文献
10.
通过硬度测试、拉伸性能测试、透射电镜观察等分析手段研究了不同强变形工艺下2519A铝合金的力学性能与微观组织。结果表明,经50%的冷轧变形和165 ℃人工时效后,2519A合金的力学性能明显提高,其抗拉强度、屈服强度和伸长率分别为522 MPa、468 MPa和8.5%。而在冷变形前添加165 ℃×2 h预时效处理,合金的力学性能进一步提高,其抗拉强度、屈服强度和伸长率分别达到535 MPa、497 MPa和8%。预时效处理可以提高合金中θ′相的密度,使析出相分布更加均匀,有助于提高合金的力学性能。 相似文献