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181.
In this paper, the dynamic observer-based controller design for a class of neutral systems with H∞ control is considered. An observer-based output feedback is derived for systems with polytopic parameter uncertainties. This controller assures delay-dependent stabilization and H∞ norm bound attenuation from the disturbance input to the controlled output. Numerical examples are provided for illustration and comparison of the proposed conditions.  相似文献   
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The numbers of multimedia applications and their users increase with each passing day. Different multi-carrier systems have been developed along with varying techniques of space-time coding to address the demand of the future generation of network systems. In this article, a fuzzy logic empowered adaptive backpropagation neural network (FLeABPNN) algorithm is proposed for joint channel and multi-user detection (CMD). FLeABPNN has two stages. The first stage estimates the channel parameters, and the second performs multi-user detection. The proposed approach capitalizes on a neuro-fuzzy hybrid system that combines the competencies of both fuzzy logic and neural networks. This study analyzes the results of using FLeABPNN based on a multiple-input and multiple-output (MIMO) receiver with conventional partial opposite mutant particle swarm optimization (POMPSO), total-OMPSO (TOMPSO), fuzzy logic empowered POMPSO (FL-POMPSO), and FL-TOMPSO-based MIMO receivers. The FLeABPNN-based receiver renders better results than other techniques in terms of minimum mean square error, minimum mean channel error, and bit error rate.  相似文献   
184.
Using mRNA to produce therapeutic proteins is a promising approach to treat genetic diseases. However, systemically delivering mRNA to cell types besides hepatocytes remains challenging. Fast identification of nanoparticle delivery (FIND) is a DNA barcode‐based system designed to measure how over 100 lipid nanoparticles (LNPs) deliver mRNA that functions in the cytoplasm of target cells in a single mouse. By using FIND to quantify how 75 chemically distinct LNPs delivered mRNA to 28 cell types in vivo, it is found that an LNP formulated with oxidized cholesterol and no targeting ligand delivers Cre mRNA, which edits DNA in hepatic endothelial cells and Kupffer cells at 0.05 mg kg?1. Notably, the LNP targets liver microenvironmental cells fivefold more potently than hepatocytes. The structure of the oxidized cholesterols added to the LNP is systematically varied to show that the position of the oxidative modification may be important; cholesterols modified on the hydrocarbon tail associated with sterol ring D tend to outperform cholesterols modified on sterol ring B. These data suggest that LNPs formulated with modified cholesterols can deliver gene‐editing mRNA to the liver microenvironment at clinically relevant doses.  相似文献   
185.
This paper discusses the delay-dependent exponential stability of a class of uncertain T-S fuzzy switched systems with time delay. The method is based on Lyapunov stability theorem and free weighting matrices approach. Two illustrative examples are given to demonstrate the effectiveness of the proposed method.  相似文献   
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Biodiesel and oxyhydrogen (HHO) gas have shown promising results in improving engine performance and emissions. In this work, the effects of HHO gas and 5% biodiesel blends (B5) and their combined use in a 315 cc diesel engine have been analyzed. Biodiesel is produced by base catalyzed transesterification and cleaned by emulsification. Its calculated cetane index (CCI) was 61.4. HHO gas is produced from electrolysis of concentrated potassium hydroxide solution. The use of 5% biodiesel blend resulted in a significant rise of 9.4% in the brake thermal efficiency (BTE) and a maximum reduction of 8.19% in the brake specific fuel consumption (BSFC). HHO enrichment of diesel and biodiesel at 2.81 L/min through the intake manifold improved the torque and power by an average of over 3%. HHO addition also improved the BTE of diesel by a maximum of 3.67%. The combination of high CCI biodiesel fuel and HHO creates a mixture that has shortened the ignition delay (ID) to the point that adverse effects were observed due to the premature combustion as shown by the average decrease in the BTE of 2.97% compared to B5. Thus, B5, on its own, is found to be the optimum fuel under these conditions.  相似文献   
188.
The purpose of our study was to investigate the biofilm formation by Legionella pneumophila serogroup1 and serogroup2-15 on plumbing materials mostly used in building water systems in Morocco. The effect of plumbing materials and temperature were examined. The Atomic Force Microscopy was used to evaluate the roughness and surface topography of the plumbing materials including galvanized steel, stainless steel, copper, Polyvinyl chloride, Polypropylene Random Copolymer and Cross-linked polyethylene. Galvanized steel surfaces supported higher numbers of bacterial cells than that the stainless steel and plastic materials at 37 than 20 and 45 °C. Non-viable counts could be obtained from the copper surfaces. L. pneumophila sg2-15 strains presented a higher ability to biofilm formation than L. pneumophila sg1. The biofilm formation was evaluated by Atomic Force Microscopy.  相似文献   
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