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101.
Self-tuning fuzzy logic controllers (STFLC) for the active control of Marmara Kocaeli earthquake excited building structures
are studied in this paper. Vibration control using intelligent controllers, such as fuzzy logic has attracted the attention
of structural control engineers during the last few years, because fuzzy logic can handle nonlinearities, uncertainties, and
heuristic knowledge effectively and easily. The improved seismic control performance can be achieved by converting a simply
designed static gain into a real time variable dynamic gain through a self-tuning mechanism. Self-tuning fuzzy logic controller
is designed to reduce the story-drift of each floor. The simulated system has a nine-degree-of-freedom, which is modeled using
nonlinear behavior of the base-structure interaction. Modeled system was simulated against the ground motion of the Marmara
Kocaeli earthquake (M
w=7.4) in Turkey on 17 August, 1999. At the end of the study, the time history of the story displacements, accelerations, ATMD
displacements, control voltage, and frequency responses of the both uncontrolled and controlled cases are presented. The robustness
of the controller has been checked through the uncertainty in stiffness of the structure. Performance of the designed STFLC
has been demonstrated for the different disturbance using ground motion of the Kobe earthquake. Simulations of an earthquake
excited nine story structure are performed to prove the validity of proposed control strategy. 相似文献
102.
Meng-Che Tu Deepa Rajwar Gopal Ammanath Palaniappan Alagappan Umit Hakan Yildiz Bo Liedberg 《Analytica chimica acta》2016
A colorimetric Al3+ sensor based on fluorescence recovery of a conjugated copolymer-ATP complex is proposed. An optimized ratio of two polythiophene (PT) monomers is utilized to synthesize copolymer (CP) that yielded maximized colorimetric response for Al3+ in deionized (DI) and tap water. The electrostatic disassembly of CP-ATP upon addition of Al3+ led to an evident visual color change. The lowest concentration of Al3+ for naked eye observation is around 4 μM, which is below the threshold levels in drinking water according to European Economic Community (EEC) standard. Besides, the proposed assay showed a similar response to Al3+ in tap water. The proposed methodology showed selective and sensitive detection for Al3+ in analytically relevant concentration ranges without involving sophisticated instrumentation, illustrating the applicability for on-site drinking water monitoring. 相似文献
103.
Hakan
im
ek 《Applied mathematics and computation》2004,150(3):833-839
Considerable attention is currently begin devoted to Cauchy problems of mathemetical physics in view of their increasing importance for the solution of applied problems [M. Taylor, Partial Differential Equations, Springer, Berlin, 1966]. Uniqueness of the solution for these problems very important. In this paper we found a bound in the uniqueness theorem for the Cauchy problem. 相似文献
104.
Critical evaluation of CFD codes for interfacial simulation of bubble‐train flow in a narrow channel
Computational fluid dynamics (CFD) codes that are able to describe in detail the dynamic evolution of the deformable interface in gas–liquid or liquid–liquid flows may be a valuable tool to explore the potential of multi‐fluid flow in narrow channels for process intensification. In the present paper, a computational exercise for co‐current bubble‐train flow in a square vertical mini‐channel is performed to investigate the performance of well‐known CFD codes for this type of flows. The computations are based on the volume‐of‐fluid method (VOF) where the transport equation for the liquid volumetric fraction is solved either by the methods involving a geometrical reconstruction of the interface or by the methods that use higher‐order difference schemes instead. The codes contributing to the present code‐to‐code comparison are an in‐house code and the commercial CFD packages CFX, FLUENT and STAR‐CD. Results are presented for two basic cases. In the first one, the flow is driven by buoyancy only, while in the second case the flow is additionally forced by an external pressure gradient. The results of the code‐to‐code comparison show that only the VOF method with interface reconstruction leads to physically sound and consistent results, whereas the use of difference schemes for the volume fraction equation shows some deficiencies. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
105.
Renée L. Beyer Hakan Kandemir Mohan Bhadbhade Ibrahim F. Sengul Chao-wei Leu Daniel Wenholz Naresh Kumar David StC. Black 《Tetrahedron letters》2018,59(51):4483-4486
Acylation reactions of 4,6-dimethoxyindoles with glyoxyloyl chlorides were achieved by the use of graphite powder in 1,2-dichloroethane at reflux. The products were monoketones as a result of decarbonylation, rather than the expected 1,2-diketones. Treatment of these monoketones with base led to their cyclisation and elimination of methanol to afford the novel dipyrrolo[2.3-a:1′,2′,3′-fg]acridin-12(1H)-ones. 相似文献
106.
107.
The novel (E,E)-dioxime 5,6:13,14-dibenzo-9,10-benzo(15-crown-5)-2,3-bis(hydroxyimino)-7,12-dioxo-1,4,8,11-tetraazacyclotetradecane (H2L) has been synthesized by the reaction of 4′,5′-diaminobenzo(15-crown-5) with N,N′-bis(2-carbomethoxyphenyl)diaminoglyoxime (1). Only mononuclear CoIII and RuII complexes with a metal/ligand ratio of 1:2 have been isolated. The cobalt(III) complex bridged with BF2+ is achieved with H-bonded cobalt(III) complex and borontrifluoride ethyl ether complex. The reaction of BF2 bridged cobalt(III) complex with bis(benzonitril)palladium(II) chloride gives a trinuclear complex. The structures of dioxime and its complexes are proposed according to elemental analyses, 1H and 13C-NMR, IR and mass spectral data. 相似文献
108.
Tuba Erdogan Eda Gungor Hakan Durmaz Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2006,44(4):1396-1403
We prepared a novel miktoarm star copolymer with an azobenzene unit at the core via combination of atom transfer radical polymerization (ATRP) and nitroxide‐mediated free radical polymerization (NMP) routes. For this purpose, first, mikto‐functional initiator, 3 , with tertiary bromide (for ATRP) and 2,2,6,6‐tetramethylpiperidin‐1‐yloxy (TEMPO) (for NMP) functionalities and an azobenzene moiety at the core was synthesized. The initiator 3 thus obtained was used in the subsequent living radical polymerization routes such as ATRP of MMA and NMP of St, respectively, to give A2B2 type miktoarm star copolymer, (PMMA)2‐(PSt)2 with an azobenzene unit at the core with controlled molecular weight and low polydispersity (Mw/Mn < 1.15). The photoresponsive properties of 3 and (PMMA)2‐(PSt)2 miktoarm star copolymer were investigated. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1396–1403, 2006 相似文献
109.
Effects of inclination angle on natural convection heat transfer and fluid flow in a two-dimensional enclosure filled with Cu-nanofluid has been analyzed numerically. The performance of nanofluids is tested inside an enclosure by taking into account the solid particle dispersion. The angle of inclination is used as a control parameter for flow and heat transfer. It was varied from = 0° to = 120°. The governing equations are solved with finite-volume technique for the range of Rayleigh numbers as 103 Ra 105. It is found that the effect of nanoparticles concentration on Nusselt number is more pronounced at low volume fraction than at high volume fraction. Inclination angle can be a control parameter for nanofluid filled enclosure. Percentage of heat transfer enhancement using nanoparticles decreases for higher Rayleigh numbers. 相似文献
110.
Selimefendigil Fatih Öztop Hakan F. 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1485-1501
Journal of Thermal Analysis and Calorimetry - Forced convection of hybrid Ag–MgO/water nanofluid in a three-dimensional T-shaped vented cavity with multiple ports under the effects of a inner... 相似文献