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Stationary process, defined

The correlation time, given by l/ eff> may be calculated exactly in the following way. Let us define the normalized correlation function of a stationary process by... [Pg.382]

Exercise. The spectral density of Campbell s process (defined by (1.9) with stationary independent ts) is... [Pg.60]

Exercise. Y(t) being the Ornstein-Uhlenbeck process define Z(t) = jo Y(t ) dt for t O. The process Z(t) is Gaussian but neither stationary nor Markovian. Show... [Pg.86]

These processes are non-stationary because the condition singled out a certain time t0. Yet their transition probability depends on the time interval alone as it is the same as the transition probability of the underlying stationary process. Non-stationary Markov processes whose transition probability depends on the time difference alone are called homogeneous processes. 10 They usually occur as subensembles of stationary Markov processes in the way described here. However, the Wiener process defined in 2 is an example of a homogeneous process that cannot be embedded in a stationary Markov process. [Pg.87]

Characteristic time Fo defines dimensionless duration of non-stationary process and in inverse proportion to a square of characteristic thickness of bed8ch and in direct ratio an effective temperature conductivity a. For example, for increase of capacity of heat process in HHP it is necessary to reduce time of process. Active reduction of physical time of process will be promoted by reduction of thickness of bed8Ch and increase in its temperature conductivity a. [Pg.387]

Nowadays the study of a reaction mechanism may be done by performing a well determined sequence of computational steps we define this sequence as the canonical approach to the study of chemical reactions. At first, one has to define the geometry of reagents and products, then that of other locally stable intermediates, especially those acting as precursors of the true reaction process, and finally that of the transition state or states and of the reaction intermediates, if any. The determination of these geometries will of course be accompanied by the computation of the relative energies. All the points on the potential energy hypersurface we have mentioned are stationary points, defined by the condition ... [Pg.12]

In this contribution we describe a framework of non-stationary Gaussian processes defined in the wavelet domain. These processes are characterized by their time dependent spectral properties and thus can be utilized to... [Pg.326]

Coherence is a normalized (so that it lies between zero and unity), cross-spectral density function that is a measure of the similarity of received signals and noise between any sensors of the array. The complex coherence functions between two wide-sense-stationary processes x and y are defined by... [Pg.1892]

For design purpose, the ground motion is usually assigned through acceleration, velocity, or displacement response spectra, while the stochastic representations discussed above are defined in terms of PSD of a parent stationary process and time-modulation functions. The relationship between these two representations is not obvious since it involves the expected maxima of the response of a sdof linear system subjected to the earthquake input, i.e., the response of the system ... [Pg.2037]

The primary nucleation process is divided into two periods in CNT one is the so called induction period and the other is the steady (or stationary) nucleation period (Fig. 2) [16,17]. It has been proposed by CNT that small (nanometer scale) nuclei will be formed spontaneously by thermal fluctuation after quenching into the supercooled melt, some of the nuclei could grow into a critical nucleus , and some of the critical nuclei will finally survive into macroscopic crystals. The induction period is defined as the period where the nucleation rate (I) increases with time f, whereas the steady period is that where I nearly saturates to a constant rate (fst). It should be noted that I is a function of N and t,I = I(N, t). In Fig. 2, N and N mean the size of a nucleus and that of the critical nucleus, respectively. The size N is defined... [Pg.137]

Fig. 3.6. One kind of stationary state, which is not an equilibrium state, is defined by a system that is not in equilibrium with its surrounding material and is not gaining or losing material or energy since the barrier is too large for change at a given temperature, full line. Dashed line is for the same process catalysed to lower the barrier allowing change, that is flow. Fig. 3.6. One kind of stationary state, which is not an equilibrium state, is defined by a system that is not in equilibrium with its surrounding material and is not gaining or losing material or energy since the barrier is too large for change at a given temperature, full line. Dashed line is for the same process catalysed to lower the barrier allowing change, that is flow.
Let us consider now processes where intermediate stationary Hamiltonians are mediating the interconversion. In these processes, there is implicit the assumption that direct couplings between the quantum states of the precursor and successor species are forbidden. All the information required to accomplish the reaction is embodied in the quantum states of the corresponding intermediate Hamiltonian. It is in this sense that the transient geometric fluctuation around the saddle point define an invariant property. [Pg.326]

The proton transfer processes described above induce interesting effects on the geometry of these metal complexes upon protonation (see also Section II). If it is assumed that the equatorial cyano ligands form a reference plane and are stationary for any of these distorted octahedral cyano oxo complexes, the protonation/deprotonation process as illustrated in Scheme 3 is responsible for the oxygen exchange at the oxo sites. This process effectively induces a dynamic oscillation of the metal center along the O-M-O axis at a rate defined by kmv, illustrated in Fig. 15. This rate of inversion is determined by the rate at which the proton is transferred via the bulk water from the one... [Pg.89]

If AW AW the process of finding a linear-mixture basis can be tedious. Fortunately, however, in practical applications Nm is usually not greater than 2 or 3, and thus it is rarely necessary to search for more than one or two combinations of linearly independent columns for each reference vector. In the rare cases where A m > 3, the linear mixtures are often easy to identify. For example, in a tubular reactor with multiple side-injection streams, the side streams might all have the same inlet concentrations so that c(2) = = c(iVin). The stationary flow calculation would then require only AW = 1 mixture-fraction components to describe mixing between inlet 1 and the Nm — I side streams. In summary, as illustrated in Fig. 5.7, a turbulent reacting flow for which a linear-mixture basis exists can be completely described in terms of a transformed composition vector ipm( defined by... [Pg.186]

Stationary source. USEPA defined source to include the entire facility. Sources are still required to submit one RMP and one registration as part of that RMP for all processes at the source with more than a threshold quantity of a regulated substance. [Pg.80]


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Stationary process

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