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The dynamic system

Let s continue with system curves. Up to this point, all elevations, temperatures, pressures and resistances in the drawings and graphs of systems and tanks have been static. This is not reality. Let s now consider the dynamic system curve and how it coordinates with the pump curve. [Pg.110]

At the beginning of the operation, the work of the pump is to complete elevation Hs], This elevation becomes Hs2 at the end of the operation. [Pg.110]


In (10), both 5i and 52 appear as independent constants. If, in addition, the dynamical system possesses some symmetry, then these numbers may satisfy a further relation. To illustrate this fact, let us consider the simplest case where we have a symmetry transformation k in the problem with k = id. Then one can show (see again [6]) ... [Pg.106]

In many cases the dynamical system consists of fast degrees of freedom, labeled x, and slow degrees of freedom, labeled y. An example is that of a fluid containing polyatomic molecules. The internal vibrations of the molecules are often very fast compared to their translational and orientational motions. Although this and other systems, like proteins, have already been treated using RESPA,[17, 34, 22, 23, 24, 25, 26] another example, and the one we focus on here, is that of a system of very light particles (of mass m) dissolved in a bath of very heavy particles (mass M).[14] The positions of the heavy particles are denoted y and the positions of the light particles rire denoted by X. In this case the total Liouvillian of the system is ... [Pg.304]

Entropy Much of the more technical discussion of the dynamical systems approach to CA in chapter 4 will depend on the notions of information and entropy. We here provide the groundwork for our later analysis by introducung the following two elementary measures ... [Pg.80]

The dynamical system F/, 7, consisting of the set of admissible sequences under / and the shift map, 7, is the n -order symbolic dynamical system induced by f The power of the method resides in the following - provided that the... [Pg.196]

As it stands, of course, the dynamical system defined by equation 8.3, is reversible- -but is clearly not a CA, since the system is, in general, neither space nor time invariant. We can restore this invariance, however, by choosing TTi t) in such a manner that its dependence on H and C is only an indirect one - specifically, so that it depends only on the particular state of the neighborhood (or landscape) of site i (excluding i itself) at time C. [Pg.373]

The exponent /3 decreases from 1.6 to 1.0 as the system size increases from N = 2 to N = 100. Kaneko suggests that this may result from an effective increase in the number cf possible pathways for the zigzag collapse, and thus that the change of 0 with size may be regarded as a path from the dynamical systems theory to statistical mechanical phase transition problems [kaneko89a]. [Pg.395]

Now we can visualize the dynamic system from the drawings. So, we are able to perfectly explain our ideas from the drawings and by using the formulae. [Pg.303]

Topaz was used to calculate the time response of the model to step changes in the heater output values. One of the advantages of mathematical simulation over experimentation is the ease of starting the experiment from an initial steady state. The parameter estimation routines to follow require a value for the initial state of the system, and it is often difficult to hold the extruder conditions constant long enough to approach steady state and be assured that the temperature gradients within the barrel are known. The values from the Topaz simulation, were used as data for fitting a reduced order model of the dynamic system. [Pg.496]

The main process variables in differential contacting devices vary continuously with respect to distance. Dynamic simulations therefore involve variations with respect to both time and position. Thus two independent variables, time and position, are now involved. Although the basic principles remain the same, the mathematical formulation, for the dynamic system, now results in the form of partial differential equations. As most digital simulation languages permit the use of only one independent variable, the second independent variable, either time or distance is normally eliminated by the use of a finite-differencing procedure. In this chapter, the approach is based very largely on that of Franks (1967), and the distance coordinate is treated by finite differencing. [Pg.221]

When the dynamic system is described by a set of stiff ODEs and observations during the fast transients are not available, generation of artificial data by interpolation at times close to the origin may be very risky. If however, we ob-... [Pg.154]

The point q = p = 0 (or P = Q = 0) is a fixed point of the dynamics in the reactive mode. In the full-dimensional dynamics, it corresponds to all trajectories in which only the motion in the bath modes is excited. These trajectories are characterized by the property that they remain confined to the neighborhood of the saddle point for all time. They correspond to a bound state in the continuum, and thus to the transition state in the sense of Ref. 20. Because it is described by the two independent conditions q = 0 and p = 0, the set of all initial conditions that give rise to trajectories in the transition state forms a manifold of dimension 2/V — 2 in the full 2/V-dimensional phase space. It is called the central manifold of the saddle point. The central manifold is subdivided into level sets of the Hamiltonian in Eq. (5), each of which has dimension 2N — 1. These energy shells are normally hyperbolic invariant manifolds (NHIM) of the dynamical system [88]. Following Ref. 34, we use the term NHIM to refer to these objects. In the special case of the two-dimensional system, every NHIM has dimension one. It reduces to a periodic orbit and reproduces the well-known PODS [20-22]. [Pg.198]

This equation has been used by Sundstrom and coworkers [151] and adapted to the analysis of femtosecond spectral evolution as monitored by the bond-twisting events in barrierless isomerization in solution. The theoretical derivation of Aberg et al. establishes a link between the Smoluchowski equation with a sink and the Schrodinger equation of a solute coupled to a thermal bath. The reader is referred to this important work for further theoretical details and a thorough description of the experimental set up. It is sufficient to say here that the classical link is established via the Hamilton-Jacobi equation formalism. By using the standard ansatz Xn(X,t)= A(X,i)cxp(S(X,t)/i1l), where S(X,t) is the action of the dynamical system, and neglecting terms in once this... [Pg.312]

Following Bortolotto et al. (1985), let us consider the dynamic system governed by the following stochastic model ... [Pg.192]

This section mainly builds upon classic biochemistry to define the essential building blocks of metabolic networks and to describe their interactions in terms of enzyme-kinetic rate equations. Following the rationale described in the previous section, the construction of a model is the organization of the individual rate equations into a coherent whole the dynamic system that describes the time-dependent behavior of each metabolite. We proceed according to the scheme suggested by Wiechert and Takors [97], namely, (i) to define the elementary units of the system (Section III. A) (ii) to characterize the connectivity and interactions between the units, as given by the stoichiometry and regulatory interactions (Sections in.B and II1.C) and (iii) to express each interaction quantitatively by... [Pg.119]

I now consider statement 3 How should an extension of dynamics be understood In the MPC theory the problem does not exist For the intrinsically stochastic systems there is no need for modifying the laws of dynamics. As for the LPS theory, one notes the presence of two essentially new concepts. The introduction of non-Hilbert functional spaces only concerns the definition of the states of the dynamical system, and not at all the law governing their evolution. It is an important precision introduced in statistical mechanics. The extension of dynamics thus only appears in the operation of regularization of the resonances. This step is also the one that is most difficult to justify rigorously it is related to the (practical) necessity to use perturbation calculus (see Appendix). [Pg.23]

In 2004, Rayner and coworkers reported a dynamic system for stabilizing nucleic acid duplexes by covalently appending small molecules [34]. These experiments started with a system in which 2-amino-2 -deoxyuridine (U-NH ) was site-specifically incorporated into nucleic acid strands via chemical synthesis. In the first example, U-NH was incorporated at the 3 end of the self-complementary U(-NH2)GCGCA DNA. This reactive amine-functionalized uridine was then allowed to undergo imine formation with a series of aldehydes (Ra-Rc), and aldehyde appendages that stabilize the DNA preferentially formed in the dynamic system. Upon equilibration and analysis, it was found that the double-stranded DNA modified with nalidixic aldehyde Rc at both U-NH positions was amplified 34% at the expense of Ra and Rb (Fig. 3.16). The Rc-appended DNA stabilizing modification corresponded to a 33% increase in (melting temperature). Furthermore, imine reduction of the stabilized DNA complex with NaCNBH, resulted in a 57% increase in T. ... [Pg.101]

Biochemical oxygen demand (BOD) is one of the most widely determined parameters in managing organic pollution. The conventional BOD test includes a 5-day incubation period, so a more expeditious and reproducible method for assessment of this parameter is required. Trichosporon cutaneum, a microorganism formerly used in waste water treatment, has also been employed to construct a BOD biosensor. The dynamic system where the sensor was implemented consisted of a 0.1 M phosphate buffer at pH 7 saturated with dissolved oxygen which was transferred to a flow-cell at a rate of 1 mL/min. When the current reached a steady-state value, a sample was injected into the flow-cell at 0.2 mL/min. The steady-state current was found to be dependent on the BOD of the sample solution. After the sample was flushed from the flow-cell, the current of the microbial sensor gradually returned to its initial level. The response time of microbial sensors depends on the nature of the sample solution concerned. A linear relationship was foimd between the current difference (i.e. that between the initial and final steady-state currents) and the 5-day BOD assay of the standard solution up to 60 mg/L. The minimum measurable BOD was 3 mg/L. The current was reproducible within 6% of the relative error when a BOD of 40 mg/L was used over 10 experiments [128]. [Pg.127]

The auxiliary discrete dynamical system for the reaction network if is the dynamical system O = defined by the map (j) on the set js/. Auxiliary reaction network f — f has the same set of vertices 22/ and the set of reactions A, A q with reaction constants k,. Auxiliary kinetics is described by... [Pg.141]

In general case, let the system have several attractors that are not fixed points, but cycles Ci, C2,... with periods ti, T2,... >1. By gluing these cycles in points, we transform the reaction network if into if. The dynamical system is transformed into Eor these new system and network, the connection... [Pg.141]

Due to its complexity, a truly integrated approach is required in designing a production rule base to provide the job description for the FMS dynamic scheduler. This is because the dynamic system relies heavily on the knowledge base as represented by the rule base, and an overly restrictive rule base will lead to inefficient, at times even wrong, decisions. In other words, such a structure should represent all the multilevel interactions and their possible precedence rules that relate to the manufacturing process planning and processing decisions in an FMS. This turns out to be a difficult task. [Pg.171]

The set of four ordinary differential equations (7.64) to (7.67) for the dynamical system are quite sensitive numerically. Extreme care should be exercised in order to obtain reliable results. We advise our students to experiment with the standard IVP integrators ode... in MATLAB as we have done previously in the book. In particular, the stiff integrator odel5s should be tried if ode45 turns out to converge too slowly and the system is thus found to be stiff by numerical experimentation. [Pg.462]

The fuel source is methane and a reformer is necessary. For this study, the reformer is externally heated such that it is not a heat load on the system. This allows one less physical feedback mechanism on the dynamic system, which will simplify the result and interpretation of the results. (For real application studies, the coupling is needed for peak efficiency reasons.)... [Pg.265]


See other pages where The dynamic system is mentioned: [Pg.1057]    [Pg.303]    [Pg.724]    [Pg.110]    [Pg.666]    [Pg.284]    [Pg.293]    [Pg.426]    [Pg.271]    [Pg.129]    [Pg.283]    [Pg.33]    [Pg.100]    [Pg.176]    [Pg.184]    [Pg.185]    [Pg.237]    [Pg.179]    [Pg.361]    [Pg.374]    [Pg.307]    [Pg.184]    [Pg.227]    [Pg.229]    [Pg.81]    [Pg.80]   


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