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Defined history

The PIVIT also has the ability to profile historical trends and project future values. Forecasts can be based on user-defined history (i.e., Months for Regression ), the type of regression (i.e., linear, exponential, or polynomial), the number of days, months, or years to forecast, and if any offset should be applied to the forecast. These features allow the user to create an unlimited number of what if scenarios and allow only the desired range of data to be applied to a forecast. In addition to the graphical display of data values, historical and projected tables are also provided. These embedded tables look and function very much like a standard spreadsheet. [Pg.851]

Because glassy polymer properties depend strongly on previous history and experimental conditions, studies on these materials require samples with well-defined histories and consistent methodologies for meaningful eompar-isons. In the aging studies described previously in this chapter, a controlled quench from above the glass transition was used to define the experimental starting time however, actual application of these materials in gas separation... [Pg.92]

Figure 5 provides an example of AE monitoring data from 22.01.1997 to 03,03.1997, in terms of time history of the main plant parameters (fig.Sa), as well as of the AE RMS values (fig. 5b). Normally, very little or no events were recorded, with the exception of the above period, in which an AE activity, very much concentrated in time and space, could be observed a sharp step in cumulative AE events takes place in a short, well defined time interval. A smaller sharp step in EA events had been observed a few days earlier, in the same position. [Pg.78]

A general prerequisite for the existence of a stable interface between two phases is that the free energy of formation of the interface be positive were it negative or zero, fluctuations would lead to complete dispersion of one phase in another. As implied, thermodynamics constitutes an important discipline within the general subject. It is one in which surface area joins the usual extensive quantities of mass and volume and in which surface tension and surface composition join the usual intensive quantities of pressure, temperature, and bulk composition. The thermodynamic functions of free energy, enthalpy and entropy can be defined for an interface as well as for a bulk portion of matter. Chapters II and ni are based on a rich history of thermodynamic studies of the liquid interface. The phase behavior of liquid films enters in Chapter IV, and the electrical potential and charge are added as thermodynamic variables in Chapter V. [Pg.1]

The definition above is a particularly restrictive description of a nanocrystal, and necessarily limits die focus of diis brief review to studies of nanocrystals which are of relevance to chemical physics. Many nanoparticles, particularly oxides, prepared dirough die sol-gel niediod are not included in diis discussion as dieir internal stmcture is amorjihous and hydrated. Neverdieless, diey are important nanoniaterials several textbooks deal widi dieir syndiesis and properties [4, 5]. The material science community has also contributed to die general area of nanocrystals however, for most of dieir applications it is not necessary to prepare fully isolated nanocrystals widi well defined surface chemistry. A good discussion of die goals and progress can be found in references [6, 7, 8 and 9]. Finally, diere is a rich history in gas-phase chemical physics of die study of clusters and size-dependent evaluations of dieir behaviour. This topic is not addressed here, but covered instead in chapter C1.1, Clusters and nanoscale stmctures, in diis same volume. [Pg.2899]

The inverse of the Cauchy-Green tensor, Cf, is called the Finger strain tensor. Physically the single-integral constitutive models define the viscoelastic extra stress Tv for a fluid particle as a time integral of the defonnation history, i.e. [Pg.87]

Vehicle volatihty requirements are a strong function of ambient temperatures. ASTM has defined five volatihty classes based on expected minimum and maximum daily temperatures. These classes and their ranges are shown in Table 3. Each month, each state is assigned a volatihty class, depending on its temperature history. Table 3 also shows the ASTM volatihty specifications for each class. [Pg.183]

Ion-selective electrodes and amperometric ceUs have had a long history of success in a wide variety of appHcations (8,9). A microelectronics-inspired revolution is also occurring in these devices, brought about by the advent of photoHthographicaHy defined arrays of microelectrodes on planar substrates... [Pg.392]

The SPE is defined as the ratio of the time required to produce a perceptible erythema on a site protected by a specified dose of the uv protectant product to the time required for minimal erythema development in the unprotected skin. An SPE of 8 indicates that the product allows a subject to expose the protected skin 8 times as long as the unprotected skin to produce the minimum erythema response. The measurement can be quite subjective unless skin color and the history of reactions to sun exposure of the test subjects are taken into account. The MED range for Caucasians at 300 nm averages 34 mj/cm. The range is 14—80 mj/cm. Perspiration or the use of artificial irradiation devices can create additional problems. [Pg.297]

The P-t histories illustrated by Fig. 2.9 are not histories of a particle of material moving with the flow, because the coordinate that is fixed is x, and material is flowing past it. A more useful P-t history would use a coordinate system which is attached to the material itself, as a stress or particle velocity gauge would be. Such a coordinate system is defined in the next section. [Pg.24]

All cost estimates are based on historical costs accumulated from previous projects. This history can be in-house, from vendors, or from the literature. The accuracy of an estimate depends on how completely the project is defined, and on how well the costs from previous projects have been analyzed and correlated. If your company does not have good (or any) past project records, the literature abounds with correlations of cost data, as discussed later. However, this data must be used very carefully. [Pg.230]

This book is primarily directed at professional materials scientists and engineers, and they have no urgent need to see themselves defined. Indeed, it would be perfectly reasonable to say about materials science what Aaron Katchalsky used to say about his new discipline, biophysics Biophysics is like my wife. I know her, but I cannot define her (Markl 1998). Nevertheless, in this preliminary canter through the early history of MSE, it is instructive to examine briefly how various eminent practitioners have perceived their changing domain. [Pg.13]

When the incidence of occupational diseases was compared with the frequency of OEL violations in Finland, a rather good correlation was observed. This indicates that these OELs are reasonably well defined. This is also natural because they are based on long-term exposure history of a large number of people. However, the OELs for many chemicals are still only educated guesses, and numerous and often large changes have been made when the OEL lists have been revised. In addition, most chemicals still have no OEL. Only about 2000 chemicals have an OEL in some country. ... [Pg.240]

The Canadian Standards Association Standard Z343 (CSA 1998) presents test methods for in-line and firebox flame arresters. In this standard in-line flame arresters are limited to only detonation types and firebox flame arresters are defined as flame arresters installed in an enclosnre, or system of enclosnres, where the mn-np distance is less than 1.5 meters and open to the atmosphere. Firebox flame arresters are commonly nsed on eqnip-ment designed to heat flnids in prodnction operations snch as indirect heaters, emnlsion treaters, and glycol dehydrators. The development history of this standard is presented in Section 2.3.2. [Pg.158]

This chapter will first cover the nature of electrophoretic separations, especially those concerning capillary electrophoresis. Comprehensive multidimensional separations will then be defined, specifically in terms of orthogonality and resolution. The history of planar and non-comprehensive electrodriven separations will then be discussed. True comprehensive multidimensional separations involving chromatography and capillary electrophoresis will be described next. Finally, the future directions of these multidimensional techniques will be outlined. [Pg.197]

There is a fundamental relationship between d-dimensional PCA and d + 1)-dimensional Ising spin models. The simplest way to make the connection is to think of the successive temporal layers of the PCA as successive hyper-planes of the next higher-dimensional spatial lattice. Because the PCA rules (at least the set of PCA rules that we will be dealing with) are (1) Markovian (i.e. the probability of a state at time t + T depends only on a set of states at time t, and (2) local, one can always define a Hamiltonian on the higher-dimensioned spatial lattice such that the thermodynamic weight of a configuration 5j,( is equal to the probability of a corresponding space-time history Si t). ... [Pg.341]

Despite the relatively short history of the chemistry of fluoride compounds, several thousands of binary and ternary fluoride compounds have been described, and their systematization is well developed [39 - 41]. Significant progress was achieved in the study of the crystal chemistry of fluoride compounds thanks to the ionic character of their chemical bonds and corresponding simplicity of their ciystal structure. The structure of these kinds of compounds is defined primarily by the geometry and the energy of mainly... [Pg.8]

It has been shown that the thermodynamic foundations of plasticity may be considered within the framework of the continuum mechanics of materials with memory. A nonlinear material with memory is defined by a system of constitutive equations in which some state functions such as the stress tension or the internal energy, the heat flux, etc., are determined as functionals of a function which represents the time history of the local configuration of a material particle. [Pg.645]

Many fluids, including some that are encountered very widely both industrially and domestically, exhibit non-Newtonian behaviour and their apparent viscosities may depend on the rate at which they are sheared and on their previous shear history. At any position and time in the fluid, the apparent viscosity pa which is defined as the ratio of the shear stress to the shear rate at that point is given by ... [Pg.104]


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See also in sourсe #XX -- [ Pg.2 , Pg.3 , Pg.4 , Pg.5 , Pg.6 , Pg.7 , Pg.8 , Pg.9 , Pg.10 , Pg.11 ]




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