Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
3 results
Search Results
Now showing 1 - 3 of 3
Article Finite-Dimensional Backstepping Controller Design(Ieee-inst Electrical Electronics Engineers inc, 2025) Kalantarov, Varga K.; Ozsari, Turker; Yilmaz, Kemal CemIn this article, we introduce a finite-dimensional version of backstepping controller design for stabilizing solutions of partial differential equations (PDEs) from boundary. Our controller uses only a finite number of Fourier modes of the state of solution, as opposed to the classical backstepping controller which uses all (infinitely many) modes. We apply our method to the reaction-diffusion equation, which serves only as a canonical example but the method is applicable also to other PDEs whose solutions can be decomposed into a slow finite-dimensional part and a fast tail, where the former dominates the evolution in large time. One of the main goals is to estimate the sufficient number of modes needed to stabilize the plant at a prescribed rate. In addition, we find the minimal number of modes that guarantee the stabilization at a certain (unprescribed) decay rate. Theoretical findings are supported with numerical solutions.Article Citation - WoS: 7Citation - Scopus: 7Comparative Analysis of Volume Change Behavior of Expansive Road Subgrades Stabilized With Waste Paper Sludge(Nature Portfolio, 2024) Tanyildizi, Muhammed; Goekalp, Islam; Zeybek, Abduelhakim; Uz, Volkan EmreExpansive soils have a high tendency for volume change in case of fluctuations in moisture content, potentially causing significant damage to light structures, particularly road pavements. This paper investigates the influence of waste paper sludge (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:WPS$$\end{document}) as an alternative sustainable stabilizer on the volume change behavior of expansive road subgrade soils of different origins. For this purpose, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:WPS$$\end{document} was added to the expansive soils at ratios of 3%, 6%, 9%, 12%, and 15% by dry weight of the soils. A series of Atterberg's limit, swelling, shrinkage, compaction, and consolidation tests were performed on pure soils and soil specimens with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:WPS$$\end{document} to attain a comprehensive understanding of the role that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:WPS$$\end{document} plays in the volume change behavior of expansive soils. The experimental test results showed that the addition of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:WPS\:$$\end{document} led to a considerable decrease in the plasticity and swell-shrink potentials of subgrade soils. The consolidation settlement of expansive road subgrades was also reduced to some extent with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:WPS$$\end{document}. Moreover, the statistical analysis of the test data indicated a significant relationship among different swelling-shrinkage parameters. The experimental results presented here suggest that the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:WPS$$\end{document} may be a cost-effective, environmentally friendly, and sustainable stabilizer to reduce the volume change sensitivity of expansive road subgrade soils.Article Citation - Scopus: 3Improvement of Strength Characteristics of a Highly Plastic Expansive Soil by Fly Ash(Sakarya University, 2022) Kodaz, G.; Demirci, H.E.; Pulat, H.F.Highly plastic expansive clays swell or shrink due to change in moisture content and they often have very low bearing capacity. Construction of engineering structures particularly pavements and lightweight buildings on problematic soils such as highly plastic expansive clays may create severe structural problems due to poor engineering properties of that kind of soil. This study focused on the influence of fly ash on strength properties of highly expansive clays which are problematic soils due to their undesirable engineering characteristics such as high plasticity index, liquid limit, swelling and shrinkage characteristics, and low bearing capacity. Atterberg’s limit tests and hydrometer tests were conducted to obtain consistency limits and grain-size distribution of the highly plastic expansive clay. Standard proctor tests for clay samples with different fly ash contents such as 10%, 15%, and 20% were performed to determine maximum dry densities and optimum water contents of the mixtures of clay and fly ash. The clay and fly ash mixtures were prepared at optimum water content and maximum dry density for unconfined compression strength (UCS) and California Bearing Ratio (CBR) tests. Effects of fly0ash content on the strength characteristics of a highly plastic expansive clay were investigated through unconfined compression and CBR tests. The experiment results showed that fly0ash is a promising additive to enhance strength characteristics of highly plastic expansive clays. An approximately 66% increase in UCS and CBR values was observed with the addition of 20% fly ash into the clay mixture in weight. © 2022, Sakarya University. All rights reserved.
