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1.
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
2.
《Geotextiles and Geomembranes》2022,50(5):1020-1035
This paper presents a numerical study on the load-bearing performance of reinforced slopes under footing load using a finite element limit analysis (FELA) method where a non-associated flow rule is assumed in the analysis. The method was validated against results from full-scale model tests and a limit equilibrium (LE) analytical method. A series of parametric analyses was subsequently carried out to examine the influences that the soil dilation angle, footing location, and reinforcement design (i.e. length, tensile strength, and vertical spacing) could have on the load-bearing performance of reinforced slopes. Results indicate that dilation angle has a significant influence on the predicted magnitudes of bearing capacity, slope deformation, and mobilized reinforcement load. The predicted values of bearing capacity using the FELA are smaller than those from the Meyerhof's analytical method for unreinforced semi-infinite foundation, especially for larger friction angle values. Additionally, the ultimate bearing capacity of the slope and its corresponding horizontal deformation increase with the reinforcement tensile strength. Finally, the slip planes under the applied footing load are found to be y-shaped and primarily occur in the upper half of the slope. 相似文献
3.
Maria Tziastoudi Georgios Pissas Georgios Raptis Christos Cholevas Theodoros Eleftheriadis Evangelia Dounousi Ioannis Stefanidis Theoharis C. Theoharides 《International journal of molecular sciences》2021,22(9)
Chronic kidney disease (CKD) is an important global public health problem due to its high prevalence and morbidity. Although the treatment of nephrology patients has changed considerably, ineffectiveness and side effects of medications represent a major issue. In an effort to elucidate the contribution of genetic variants located in several genes in the response to treatment of patients with CKD, we performed a systematic review and meta-analysis of all available pharmacogenetics studies. The association between genotype distribution and response to medication was examined using the dominant, recessive, and additive inheritance models. Subgroup analysis based on ethnicity was also performed. In total, 29 studies were included in the meta-analysis, which examined the association of 11 genes (16 polymorphisms) with the response to treatment regarding CKD. Among the 29 studies, 18 studies included patients with renal transplantation, 8 involved patients with nephrotic syndrome, and 3 studies included patients with lupus nephritis. The present meta-analysis provides strong evidence for the contribution of variants harbored in the ABCB1, IL-10, ITPA, MIF, and TNF genes that creates some genetic predisposition that reduces effectiveness or is associated with adverse events of medications used in CKD. 相似文献
4.
电信业的客户投诉不断增多而又亟待高效处理。针对电信客户投诉数据的特点,提出了一种面向高维数据的改进的集成学习分类方法。该方法综合考虑客户投诉中的文本信息及客户通讯状态信息,基于Random Subspace方法,以支持向量机(Support Vector Machine,SVM)为基分类器,采用证据推理(Evidential Reasoning,ER)规则为一种新的集成策略,构造分类模型对电信客户投诉进行分类。所提模型和方法在某电信公司客户投诉数据上进行了验证,实验结果显示该方法能够显著提高客户投诉分类的准确率和投诉处理效率。 相似文献
5.
6.
在调研当前食品农产品质量安全问题舆情风险评估研究现状基础上,面向我国农产品质量安全监管工作,从媒体关注度、网民关注度、内容敏感度和负面情绪聚集度4个角度提出了农产品质量安全舆情风险综合评估体系,并通过科学方法确立的指标体系的权重分布和不同指标数值的隶属度子集情况,推导得出一定时期内某一农产品质量安全问题事件的舆情风险综合指数公式。该指数的提出在国内具有首创性,对我国农产品质量安全舆情监管及相关研究工作具有一定的借鉴和指导意义。 相似文献
7.
Significant emergency measures should be taken until an emergency event occurs. It is understood that the emergency is characterized by limited time and information, harmfulness and uncertainty, and decision-makers are always critically bound by uncertainty and risk. This paper introduces many novel approaches to addressing the emergency situation of COVID-19 under spherical fuzzy environment. Fundamentally, the paper includes six main sections to achieve appropriate and accurate measures to address the situation of emergency decision-making. As the spherical fuzzy set (FS) is a generalized framework of fuzzy structure to handle more uncertainty and ambiguity in decision-making problems (DMPs). First, we discuss basic algebraic operational laws (AOLs) under spherical FS. In addition, elaborate on the deficiency of existing AOLs and present three cases to address the validity of the proposed novel AOLs under spherical fuzzy settings. Second, we present a list of Einstein aggregation operators (AgOp) based on the Einstein norm to aggregate uncertain information in DMPs. Thirdly, we are introducing two techniques to demonstrate the unknown weight of the criteria. Fourthly, we develop extended TOPSIS and Gray relational analysis approaches based on AgOp with unknown weight information of the criteria. In fifth, we design three algorithms to address the uncertainty and ambiguity information in emergency DMPs. Finally, the numerical case study of the novel carnivorous (COVID-19) situation is provided as an application for emergency decision-making based on the proposed three algorithms. Results explore the effectiveness of our proposed methodologies and provide accurate emergency measures to address the global uncertainty of COVID-19. 相似文献
8.
针对现有电动阀门控制系统可嵌入性差的问题,设计了一种基于CAN总线的网络化、多通道、开度型阀门嵌入式控制系统。其中,上位机主要用于下达各阀门开度等控制指令并同时监测其工作状态,而下位机采用双MCU架构,主MCU用于控制各阀门的开度大小,从MCU负责采集开度反馈电流以实现闭环控制。下位机采用了模糊PID算法进行控制参数的动态整定,可满足阀门在不同工况下的控制精度要求,并通过OLED屏显示各通道阀门的实际开度值。实验表明,该控制系统运行稳定,能实现对多通道开度阀的精准控制,控制精度在0.6%以内,并支持远程上位机控制和现地控制等多种工作模式。 相似文献
9.
采用伪布尔模型和启发式算法来求解无容量设施选址问题。首先给出了问题的伪布尔(pseudo-Boolean)表示,然后基于Khumawala规则对问题进行预处理,最后提出两种启发式分支准则来求解问题。实验结果表明所提算法简单有效。 相似文献
10.
基于形式美对比法则、均衡法则、韵律法则的内涵及其在针织面料设计中的应用规律,从深浅、虚实、肌理、曲直、高低等视角选取典型案例对针织面料进行分析,得出针织面料在形式上具有的独特意趣与艺术价值,并探讨其形式美及审美意义。通过分析针织技术与形式美法则之间的关联,探寻针织面料中形式美法则的作用及其基本规律与原理,以此指导针织面料的设计,为现代设计师灵活运用形式美法则进行艺术创作提供一定的参考。 相似文献