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Linear memory

The function g(r — r ), the so-called linear memory function55> describes the bonding of units into a chain, ip(r) is the external field into which the macromolecule is placed. In a limited volume, the spectrum of eigenvalues in Eq. (3.3) is discrete therefore, for sufficiently high N... [Pg.143]

The equation leads to the definition of a time and strain-dependent memory fimction which can be further factorized into a time-dependent part (the linear memory function) and a strain-dependent damping function. Though on one hand, there is some experimental evidence for this in limited time ranges, on the other hand, a few experiments might question this strong hypothesis since, for example, the damping function obtained fi um step shear rate data is found to be different from that in step shear strain. [Pg.191]

The first term comes from the entropy and takes implicitly into account the fact that we deal with a chain (linear memory) the second term comes from the energy and is derived from the properties of a monomer solution. With Lifshitz, we grant that the equilibrium concentration is given by the functional derivative... [Pg.671]

Thus, it turns out that if you start to look into the physics of systems with linear memory (to use our teacher s word), you may hope one day to come face to face with the mysteries of biology. We shall talk more about this in the chapters that follow. [Pg.82]

Having sorted out the covalent bonds between the neighbors, we can now concentrate on all the other interactions. These are frequently referred to as volume interactions . As we have said, they have a typical energy E-2, and are much weaker than those in charge of the linear memory. In the crudest theory, we may completely neglect them. Then we shall end up with exactly what is called an ideal polymer chain. This is just how we handled all the calculations in the previous chapters. It worked fairly well, and we coped with quite a number of problems. We described how a chain rolls up into a loose coil, and we revealed the peculiar entropic nature of the high elasticity of polymers. [Pg.148]

In metallic systems, another important constitutive linear relationship has to be taken into account the free current density ] f which is generated by the electric field E. The free current density is added to the external current density in Eq. (1.4). For linear, memory-less, and isotropic media we have... [Pg.4]

Overall, we have indicated that materials exhibit complicated behavior in the glass transition region. Such effects as time dependence, asymmetry, non-linearity, memory and complex Xg behavior must be clearly explained by any successful theory. [Pg.277]

In Equation (1.28) function M(t - r ) is the time-dependent memory function of linear viscoelasticity, non-dimensional scalars 4>i and 4>2 and are the functions of the first invariant of Q(t - f ) and F, t t ), which are, respectively, the right Cauchy Green tensor and its inverse (called the Finger strain tensor) (Mitsoulis, 1990). The memory function is usually expressed as... [Pg.13]

One of the major selling points of Q-Chem is its use of a continuous fast multipole method (CFMM) for linear scaling DFT calculations. Our tests comparing Gaussian FMM and Q-Chem CFMM indicated some calculations where Gaussian used less CPU time by as much as 6% and other cases where Q-Chem ran faster by as much as 43%. Q-Chem also required more memory to run. Both direct and semidirect integral evaluation routines are available in Q-Chem. [Pg.340]

Choose the DIIS SCF convergence accelerator to potentially speed up SCF convergence. DIIS often reduces the number of iterations required to reach a convergence limit. However, it takes memory to store the Fock matrices from the previous iterations and this option may increase the computational time for individual iterations because the Fock matrix has to be calculated as a linear combination of the current Fock matrix and Fock matrices from previous iterations. [Pg.112]

Elastomers or rubbers are almost-linear polymers with occasional cross-links in which, at room temperature, the secondary bonds have already melted. The cross-links provide the "memory" of the material so that it returns to its original shape on unloading. The common rubbers are all based on the single structure... [Pg.221]

Via an ad hoc extension of the viscoelastic Hertzian contact problem, Falsafi et al. [38] incorporated linear viscoelastic effects into the JKR formalism by replacing the elastic modulus with a viscoelastic memory function accounting for time and deformation, K t) ... [Pg.127]

The second main category of neural networks is the feedforward type. In this type of network, the signals go in only one direction there are no loops in the system as shown in Fig. 3. The earliest neural network models were linear feed forward. In 1972, two simultaneous articles independently proposed the same model for an associative memory, the linear associator. J. A. Anderson [17], neurophysiologist, and Teuvo Kohonen [18], an electrical engineer, were unaware of each other s work. Today, the most commonly used neural networks are nonlinear feed-forward models. [Pg.4]

The theories of elastic and viscoelastic materials can be obtained as particular cases of the theory of materials with memory. This theory enables the description of many important mechanical phenomena, such as elastic instability and phenomena accompanying wave propagation. The applicability of the methods of the third approach is, on the other hand, limited to linear problems. It does not seem likely that further generalization to nonlinear problems is possible within the framework of the assumptions of this approach. The results obtained concern problems of linear viscoelasticity. [Pg.646]

The "add-to-memory" signal averaging method currently available to us distorts fluorescence intensity versus time plots when the fluorescence intensity is a non-linear function of incident laser energy and the laser energy varies from shot to shot. For this reason we have not attempted detailed kinetic modelling of the observed fluorescence intensity decay curves recorded at high 532 nm laser fluence. [Pg.166]

Adjustable Workbench (PAW) instrument assembly. The SH shown in Figs. 3.15 and 3.16 contains the electromechanical transducer (mounted in the center), the main and reference Co/Rh sources, multilayered radiation shields, detectors and their preamplifiers and main (linear) amplifiers, and a contact plate and sensor. The contact plate and contact sensor are used in conjunction with the IDD to apply a small preload when it places the SH holding it firmly against the target. The electronics board contains power supplies/conditioners, the dedicated CPU, different kinds of memory, firmware, and associated circuitry for instrument control and data processing. The SH of the miniaturized Mossbauer spectrometer MIMOS II has the dimensions (5 x 5.5 x 9.5) cm and weighs only ca. 400 g. Both 14.4 keV y-rays and 6.4 keV Fe X-rays are detected simultaneously by four Si-PIN diodes. The mass of the electronics board is about 90 g [36],... [Pg.55]


See other pages where Linear memory is mentioned: [Pg.4]    [Pg.209]    [Pg.2]    [Pg.172]    [Pg.670]    [Pg.317]    [Pg.190]    [Pg.81]    [Pg.147]    [Pg.148]    [Pg.343]    [Pg.592]    [Pg.1542]    [Pg.161]    [Pg.335]    [Pg.358]    [Pg.23]    [Pg.4]    [Pg.209]    [Pg.2]    [Pg.172]    [Pg.670]    [Pg.317]    [Pg.190]    [Pg.81]    [Pg.147]    [Pg.148]    [Pg.343]    [Pg.592]    [Pg.1542]    [Pg.161]    [Pg.335]    [Pg.358]    [Pg.23]    [Pg.1425]    [Pg.2974]    [Pg.314]    [Pg.345]    [Pg.464]    [Pg.71]    [Pg.116]    [Pg.347]    [Pg.450]    [Pg.163]    [Pg.37]    [Pg.44]    [Pg.406]    [Pg.149]    [Pg.121]    [Pg.272]    [Pg.30]   
See also in sourсe #XX -- [ Pg.143 ]

See also in sourсe #XX -- [ Pg.80 , Pg.148 ]




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