vibration reduction via the boundary control method

... is then minimised This is the well known Finite Element Method In the alternative (proposed by Trefftz2), the assumed functions satisfy the DE exactly and the error in the satisfaction of the boundary ... it has the character of lightness J.W von Goethe 2.1 STRATEGIES Although the first idea which provided the background for the boundary element method dates back to the early 1900s, the method ... returns the result to F The KIND of the arrays would have to match the Fortran REAL*8 precision The significance of the other parameters need not concern the applications programmer 26 The Boundary...

Ngày tải lên: 13/08/2014, 08:21

... shows the variation of the fundamental solution for the boundary traction in x-direction assuming that the vector normal to the boundary, n , points in the xdirection (this means that the computed ... depends on the current state and can therefore only be written in incremental form These problems are therefore dependent on the deformation (thermal) history As outlined previously, for the boundary ... figure 4.10) 88 The Boundary Element Method with Programming The fundamental solutions for the tractions are obtained by first computing the fundamental solutions for the strains and then applying...

Ngày tải lên: 13/08/2014, 08:21

... solve the boundary value problem (b) by the Trefftz method To apply the Trefftz method, we quite arbitrarily select N points on the boundary of the isolator, where we wish to satisfy the boundary ... potential problems either t or u must be known 132 The Boundary Element Method with Programming on the boundary, there will be as may unknowns as there are nodes In the simplest numerical method, also ... one where the solution is obtained for the following boundary condition: t (b ) t (a) q0 sin (5.5) If the two solutions for the flow normal to the boundary of the isolator are added then: t t...

Ngày tải lên: 13/08/2014, 08:21

... all boundary elements The second part of the SUBROUTINE deals with the case where Pi is one of the nodes of the element which we integrate over To deal with the singularity of the integrand the ... Gauss 144 The Boundary Element Method with Programming Quadrature The integral of the second product only exists as a Cauchy principal value However, these are the diagonal terms of the coefficient ... In the same plane as the element (d) perpendicular to the centre of the element for values of R/L= 0.5, 0.1 , 0.05 Compare with the analytical solution using MATHEMATICA or similar 168 The Boundary...

Ngày tải lên: 13/08/2014, 08:21

... the size of the system is significantly smaller The output from the program consists only of the values of the unknown at the boundary The unknown are either the temperature/displacement or the ... normal to 200 The Boundary Element Method with Programming the boundary/ boundary stresses The computation of the complete flow vectors/stress tensor at the boundary, as well as the computation ... zeroes The other difference with the FEM is that the stiffness matrix is not symmetric This has been claimed as one of the disadvantages of the method However, this is more than compensated by the...

Ngày tải lên: 13/08/2014, 08:21

... convergence of the algorithm In the case where a contour does not start from the boundary a search for the starting point of the contour may be carried out from the boundary Further details can ... 260 The Boundary Element Method with Programming The error of the prediction determined as f ( x1 , y1 ) f1 (9.59) This error is now corrected using the direction n computed at the point Further ... Compared are the maximum deflection at the free end and the bending stresses at the fixed end Note that the maximum bending stresses are obtained directly from the analysis (these are equal to the tractions...

Ngày tải lên: 13/08/2014, 08:21

... implement the method we have also laid the groundwork for the coupling with the finite element method so that there is not much more theory to discuss in Chapter 16 The multi-region method extends the ... 306 The Boundary Element Method with Programming 11.3.1 Subroutine Stiffness_BEM The tasks for the Stiffness_BEM are essentially the same as for the General_Purpose_BEM, except that the boundary ... 332 The Boundary Element Method with Programming We now investigate the other possibilities for the location of Pi Pi is located at one of the discontinuous nodes inside the element and the...

Ngày tải lên: 13/08/2014, 08:21

... be the same The geometry of these single region meshes is shown in Figure 12.15 Only the boundary of the excavated part is discretised and the excavation is done in one single step As the boundary ... first the information about the number of cell nodes, cells and the initial strain to be applied Then the coordinates of the cell nodes and the incidences of the cells are read in Next the additional ... 382 The Boundary Element Method with Programming would have to cover the entire domain, including the part where no swelling occurs Also note that the number of unknowns at the nodes of the boundary...

Ngày tải lên: 13/08/2014, 08:21

... change the boundary shape (large displacement problems) Finally, the third no longer holds true for contact problems, where either the 408 The Boundary Element Method with Programming Dirichlet boundary ... the boundary due to the higher singularity of the integral We have already presented an alternative method for computing the stress tensor on the boundary itself using the variations of the displacements ... Further examples of the application of the method to the modelling of faulted rock can be found in [12,13] The method can also be applied to the simulation of dynamic crack propagation14 432 The...

Ngày tải lên: 13/08/2014, 08:21

... the time-dependent 448 The Boundary Element Method with Programming displacements at the top of the column obtained from the analysis The results compare well with a reference solution with the ... through the end of the powerhouse Figure 17.25 View showing the concrete powerhouse and the location of the cracks 470 The Boundary Element Method with Programming Figure 17.26 shows one result of the ... the first analysis the strain in the direction of the rock bolt is computed Because of the difference in moduli between the rock and the bolt the stress is different at a point depending if the...

Ngày tải lên: 13/08/2014, 08:21

... are not the solutions of 3.60 and α t < β t , t ∈ 0, Also, the assumptions of Theorem 3.1 are satisfied Thus, the conclusion of Theorem 3.1 applies to the problem 3.60 Acknowledgment The author ... by Theorems 2.2 and 2.3, there exists a unique solution α1 of 3.16 such that α0 ≤ α1 ≤ β t , α1 ≤ M1 , t ∈ 0, 3.18 Boundary Value Problems Note that the uniqueness of the solution follows by Theorem ... f φ Then, the convergence of the sequence {αn } of approximate solutions (obtained in Theorem 3.1) is quadratic Proof Let us set en pen − qen x t − αn t 1 t ≥ so that en ηi , satisfies the boundary...

Ngày tải lên: 21/06/2014, 11:20

... point, then the sum of control coefficients would add up to )1 (as they for the control on the cell division time) The four steps delaying the RP the most (i.e with the highest positive control ... the proposal that RP control by the reaction steps works via the cyclin E/Cdk2:p27 complex The method that we have used to quantify the control of a reaction step on any of the systems variables ... moderate control (jCiRP j < 1) Eight reaction steps exerted a high control (jCiRP j > 2) on the RP; four of which caused a delay (positive control) , whereas the others advanced the RP (negative control) ...

Ngày tải lên: 15/03/2014, 09:20

... Ampr, Kanr K pneumoniae nifLA under the control of the tac promoter K pneumoniae nifA under the control of tac promoter K pneumoniae malE-nifL under the control of the tac promoter EcoRI/HindIII fdnG ... detector and the reduction of the flavin moiety of the protein was monitored at 450 nm The inset shows the difference spectrum; the fully oxidized spectrum at 10 was corrected vs the reduced spectrum ... oxidoreductase We further analyzed the effect of inside-out vesicles on the reduction state of NifL to obtain evidence for NifL reduction by NADH via a membrane-bound oxidoreductase of the anaerobic...

Ngày tải lên: 17/03/2014, 10:20

... function of the measurement vector y(t) The control problem is to find the active control force u(t) necessary to reduce the norm state vector It is seen obviously that the best control law is ... identification algorithm The numerical simulations are taken when the sensor is placed at the distances L/4, L/2 and L from the base In Fig 3, the shapes of the 1st mode, the 3rd mode and the 5th mode are ... term The magnitude of the error term depends on the number and the locations of the sensors The numerical simulation is applied to a base excited cantilever beam to illustrate the algorithm The...

Ngày tải lên: 28/03/2014, 13:20

... function of the measurement vector y(t) The control problem is to find the active control force u(t) necessary to reduce the norm state vector It is seen obviously that the best control law is ... identification algorithm The numerical simulations are taken when the sensor is placed at the distances L/4, L/2 and L from the base In Fig 3, the shapes of the 1st mode, the 3rd mode and the 5th mode are ... term The magnitude of the error term depends on the number and the locations of the sensors The numerical simulation is applied to a base excited cantilever beam to illustrate the algorithm The...

Ngày tải lên: 28/03/2014, 13:20

... summarize the impact of the channel estimation error on the D-optimal MUD as follows (i) The factors 1/(1 + ∆2 ) in (31) and − ∆2 in the nuh h merator of (32) represent the impact of the error of the ... and the overbar denotes the average over the randomness of the equivalent spreading codes It should be noted that the second equation is based on the self-averaging assumption [11] To evaluate the ... distinguished by whether or not the receiver considers the distribution of the channel estimation error We denote the case of directly using the channel estimates for MUD by a prefix D, and the case of...

Ngày tải lên: 23/06/2014, 00:20

... loads In the initial design stage, structural designers judge whether or not to apply the collapse control design method, taking into account the risk of explosions and airplane crashes in the building ... account the degree of risk involved and the importance of the building, i.e the effect it would have in the case of collapse The British Standards and Building Standards [2] prescribe the prevention ... spreading into the core section During basic design, the selection of the frame system parallels the arrangement of the core Fig shows frame deformation after the loss of three columns on the 1st floor...

Ngày tải lên: 28/06/2014, 13:49

... (1974)  As the wave number ka increases The wave forces on the cylinders oscillate around the wave forces on an isolated cylinder  As the cylinder spacing increases, the wave force on the cylinders ... to the wave force on an isolated cylinder, however it oscillates around the wave force on an isolated cylinder The amplitude of oscillation is extremely large as the ratio   0.2  Due to the ... incident wave  Y D X  2a Run-up on the outer walls of the cylinders in two transverse cylinders for ka  1.0 incident wave Y  X 2a  D Run-up on the outer walls of the cylinders in two tandem cylinders...

Ngày tải lên: 26/07/2014, 07:20

... Hence after pulling out a common denominator, we see that ωs too has the form (∗) This proves the Proposition
Theorem 1: ([Z], Theorem 7, p.596) For any WZ pair (F,G) ∞ ∞ n=0 n−1 (F (n, n − 1) ... lim F (s(n + 1), n) + n→∞ i=0 F (sn, k) k=0 Proof: Apply Theorem above on ωs Alternatively, integrate ω along the boundary contour ∂Ωs of the region Ωs = {(n, k) : sn ≥ k}
Formula 2: We also ... (n, k) = n=0 k→∞ G(n, k), n=0 whenever both side converge Proof: Integrate ω along the boundary contour ∂Ω0 of the region Ω0 = {(n, k) : n ≥ 0, k ≥ 0}

 
     
  ...

Ngày tải lên: 07/08/2014, 06:22

... some classical constants by the Markov-WZ method, J Discrete Mathematics and Theoretical Computer Science (2005), 11-24 [10] M Mohammed, D Zeilberger, The Markov-WZ method, Electronic J Combinatorics ... Proposition 1, the theorem follows Theorem Let a be a complex number not equal to a non-zero integer Then ∞ k=1 ∞ n−1 (−1)n−1 p(n, a) =2 − a2 ) − a2 )(4n2 − a2 ) 2n k(k (n n=1 n m=1 n the electronic ... MarkovWZ together with examples of accelerating formulae available from the second author’s website Many other new representations for log 2, ζ(2), ζ(3) were found in [9] In all the proofs considered...

Ngày tải lên: 07/08/2014, 15:23