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Finite element model updating using Lagrange interpolation

)+M_{a}P(0) \end{array}$$ The updating method is performed when the information matrix P and its derivatives P and P̈ are known. It is well indicated that these matrices are to be determined from the measurement components. 3 Expression for the information matrices The principal idea in this section is to interpolate the information matrices for each s-value using Eq. (4) . Suppose that “ m ” measurements are performed for a set of complex frequencies { s 0 , s i , s 2 , …, s m −1 , s m }, we have then “ m ” equation of the form Y a ( s i

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Experimental study on mechanical behavior of natural hybrid composites filled with ground nut shell ash

diverse applications ranging from aerospace to sporting equipment. The FRP composites primarily consist of synthetic fibers like glass, carbon, aramid and Kevlar. Although the synthetic fiber reinforced composites have excellent strength and hardness, they are high cost and non-biodegradable. Because of these reasons, over the past few years, the synthetic fibers have been replaced with natural fibers. The growing interest in using the natural fibers is due to their availability, satisfactory specific strength and modulus, light weight, low cost and biodegradability

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Simulation of impedance measurements at human forearm within 1 kHz to 2 MHz

which is an invasive method and cannot readily measure beat-to-beat changes. Electrical impedance measurements at the forearm provide a possible way to characterize hemodynamics, and in particular changes in the amount of blood in the arm as a result of vasodilatation and/or the cardiac cycle. Although the simulation perspective to bioimpedance plethysmography is a rarity there have been several investigations pertaining to the impedance response at forearm section. Some works [ 13 , 14 , 15 , 16 ] related to multi-frequency electrical bioimpedance (MF-EBI) for

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Aging concrete structures: a review of mechanics and concepts

micro-structure, also on the permeability and, thus, durability. Recently, the so-called gradient concrete characterized by a gradual change of density and strength throughout the cross-section is also gaining attraction. With the rapid progress in 3D printing, such a material may soon become reality ( Herrmann and Sobek, 2016 ; Strieder et al., 2018 ), thus, improving durability, serviceability and sustainability alike. Major potential for more durable and sustainable concrete structures can be expected following a successful conclusion of research on self

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Vibration analysis of functionally graded tapered rotor shaft system

rotating composite shaft based on the p-version of the finite element method. [ 8 ] studied the free vibration analysis of thick FGM plates on elastic bases with two parameters [ 9 ]. He mainly deals with the dynamic analysis of a rotor made of FGM supported on two flexible bearings, he used the finite element method based on the theory of Timoshenko (TBT) [ 10 ]. He proposed a new element for analyzing conical beams with an arbitrarily variant cross-section of a functionally classified material, [ 11 ]. He has analyzed rotor vibration and stability in FGM and takes into

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Shear Strength Enhancement of Cemented Reinforced Sand: Role of Cement Content on the Macro-Mechanical Behavior

dimension of 60 x 60 mm horizontal cross section; the height of the test piece was 25 mm. All tests were performed according to the standard ASTM D-3080 (2005) with a constant horizontal shear rate of 1.00 mm/min. Shear stress was recorded as a function of horizontal displacement to an average shear strain of 13%. The first series in this laboratory study concerned shear tests on unreinforced Chlef sand with different water contents ω = 3, 7 and 10%, the second series carried out involved 108 tests on a mixture of sand-cement with a cement content Cc = 2.5, 5

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A LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) for biological tissue impedance analysis and equivalent circuit modelling

circuit model of a single cell [ 6 , 13 , 64 , 65 , 66 , 67 , 68 , 69 , 70 ,], as described in the following sections. Animal cells can be modeled with an equivalent circuit concept as shown in Figure 4 . The resistive path created by the ICF in biological cells to an electric signal ( Figure 4a) is represented as a resistive element called ICF resistance (R ICF ). Alternatively, the capacitance [ 74 ] offered by the protein-lipid-protein structure [ 62 , 63 ] of the cell membrane is modeled as cell membrane capacitance (C CM ) [ 5 , 6 ] ( Figure 4a

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Pullout Capacity Of Cylindrical Block Embedded In Sand

, entirely flexible tendon. The tendon is attached at a distance h, below the block’s top surface. Figure 3 Geometry of the problem The horizontal ground surface is not loaded. The elastic – perfectly plastic Mohr-Coulomb model was assumed for the sand surrounding the block and the linear elastic model for concrete of the anchor block. The parameters of both models are listed in Table 1 . Table 1 Material parameters. sand concrete Young Modulus E [MPa] 80 30000 Poisson’s ratio ν [-] 0.25 0

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Centers: their integrability and relations with the divergence

that ∆( x , y ) ≥ 0 or ∆( x , y ) ≤ 0 for all ( x , y ) ∈ ℝ 2 . For more details on characteristic directions see for instance [ 2 ]. 5 Poincaré–Liapunov constants Suppose that the analytic differential system 1 has a monodromic singular point at the origin O . Let Σ be an analytic transversal section at O , that is, an analytic arc transverse to the flow of the system such that O ∈ ∂ Σ, the boundary of Σ. We consider a parameter ρ of Σ such that ρ = 0 corresponds to the origin of coordinates and Σ is parameterized by the interval (0, ρ *) with ρ

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Effect of Tunnel Progress on the Settlement of Existing Piled Foundation

plastic shearing due to deviatoric loading with shear/frictional hardening (deviatoric yielding). For the deviatoric yielding a non-associated and for the cap plasticity an associated plastic flow rule is prescribed. Table 1 Concrete parameters adopted in the numerical analysis. Parameters Values Units Model Pile Pile cap Tunnel lining TBM shield Diameter (D) 1 - - - m Linear Thickness (t) - 1 0.25 0.35 m elastic Elasticity modulus (E) 30×10 6 30×10 6 30×10 6 210×10 6 kN / m 2 kN / m 3

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