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Models common purpose

However, our proposed modeling methodology is of great benefit to refiners as they can align their long and medium plans through a common purpose model. [Pg.68]

A collaboration is a set of related actions between typed objects playing certain roles with respect to others in the collaboration, within a common model of attributes. The actions are grouped into a collaboration so as to indicate that they serve a common purpose. Typically, the actions are used in different combinations to achieve different goals or to maintain an invariant between the participants. Each role is a place for an object and is named relative to the other roles in the overall collaboration. [Pg.197]

In PAT, the most common purpose of quantitative model building is to convert a nonselective analyzer into a selective one, to enable its effective use for a specific application. There are several different quantitative model building tools that have been shown to be effective for PAT applications, and these will be discussed in this section. [Pg.377]

In the following sections, I review a few, commonly-cited models of widespread compressional and extensional deformation and consider their respective elevation predictions. This review is not meant to be an exhaustive list of all possible mechanisms of elevation change due to continental deformation. Rather, the purpose is to illustrate the role of elevation as a parameter that can be used to constrain mechanisms of continental deformation. [Pg.6]

For a turbulence model to be useful in a general-purpose CFD code, it must be simple, accurate, economical to run, and have a wide range of applicability. Table 10-1 gives the most common turbulence models. The classical models use the Reynolds equations and form the basis of turbulence calculations in currently available commercial CFD codes. Farge eddy simulations are turbulence models where the time-dependent flow equations are solved for the mean flow and the largest eddies and where the effects of the smallest eddies are modeled. [Pg.794]

In the resolution of any multicomponent system, the main goal is to transform the raw experimental measurements into useful information. By doing so, we aim to obtain a clear description of the contribution of each of the components present in the mixture or the process from the overall measured variation in our chemical data. Despite the diverse nature of multicomponent systems, the variation in then-related experimental measurements can, in many cases, be expressed as a simple composition-weighted linear additive model of pure responses, with a single term per component contribution. Although such a model is often known to be followed because of the nature of the instrumental responses measured (e.g., in the case of spectroscopic measurements), the information related to the individual contributions involved cannot be derived in a straightforward way from the raw measurements. The common purpose of all multivariate resolution methods is to fill in this gap and provide a linear model of individual component contributions using solely the raw experimental measurements. Resolution methods are powerful approaches that do not require a lot of prior information because neither the number nor the nature of the pure components in a system need to be known beforehand. Any information available about the system may be used, but it is not required. Actually, the only mandatory prerequisite is the inner linear structure of the data set. The mild requirements needed have promoted the use of resolution methods to tackle many chemical problems that could not be solved otherwise. [Pg.419]

A key point in the simulations is the choice of the interaction potential. There exist many different water models optimized for different purposes.Each model shows better or worse agreement with particular water properties. These models are mostly fitted to describe liquid water. Therefore, their use for the simulations of ice can be tricky. Namely, one of the properties that is often described incorrectly is the melting temperature. A comprehensive comparison of the most common water models with respect to the melting temperature of water has been published recently. Values in the wide range of 190-270 K were obtained. It is, therefore, always necessary to choose between the computer efficiency of the model and the quality of the description of water properties, although a more complicated model does not always mean better description. [Pg.628]

The purpose of this chapter is to present several of the most common models used to describe metal and metalloid ion adsorption by soil components. Empirical models used in soil chemistry are described and their limitations discussed. Common chemical models used to describe metal adsorption on soil minerals are described and their advantages over empirical approaches discussed. Methods for obtaining model parameters are provided. Methods for establishing adsorption mechanisms and surface speciation are addressed. Limitations and approximations in the application of chemical models to natural systems are presented. [Pg.216]

First we will examine the issue of phrasing prediction, which is how to generate a prosodic phrase structure for a sentence from the text. For purposes of illustration we will adopt the model described in Section 6.2.2, where we have a major phrase and a minor phrase. This is probably the most commonly used model in TTS. [Pg.129]

Diffusion is the mass transfer caused by molecular movement, while convection is the mass transfer caused by bulk movement of mass. Large diffusion rates often cause convection. Because mass transfer can become intricate, at least five different analysis techniques have been developed to analyze it. Since they all look at the same phenomena, their ultimate predictions of the mass-transfer rates and the concentration profiles should be similar. However, each of the five has its place they are useful in different situations and for different purposes. We start in Section 15.1 with a nonmathematical molecular picture of mass transfer (the first model) that is useful to understand the basic concepts, and a more detailed model based on the kinetic theory of gases is presented in Section 15.7.1. For robust correlation of mass-transfer rates with different materials, we need a parameter, the diffusivity that is a fundamental measure of the ability of solutes to transfer in different fluids or solids. To define and measure this parameter, we need a model for mass transfer. In Section 15.2. we discuss the second model, the Fickian model, which is the most common diffusion model. This is the diffusivity model usually discussed in chemical engineering courses. Typical values and correlations for the Fickian diffusivity are discussed in Section 15.3. Fickian diffusivity is convenient for binary mass transfer but has limitations for nonideal systems and for multicomponent mass transfer. [Pg.603]

The small example systems considered in this chapter are widely used basic components of power electronic systems. In power electronics, it is common to model the fast switching semiconductor devices that use various types of transistors, diodes, or thyristors simply as ideal or non-ideal switches although more sophisticated transistor models can be used and are used depending on the application and the purpose of a simulation study. [Pg.216]

To put every scenario on a common basis, CGR Management Consultants and SFI developed a common cost model. Its purpose was to eliminate these differences when evaluating the underlying changes in location. The model, called SITELINK, used a structure that is adaptable for supply chain network optimization modeling. Figure 44.1 is a simplified stmcture of the SITELINK model. [Pg.503]

The Pearl GTL plant consists of more than 80 separate process units for 2 separate production trains and common utilities. Modeling the whole plant and creating a complete virtual planf was neither considered feasible nor a requirement and the approach was therefore to make a fit-for-purpose MPDS. Approximately 35 units of 1 single train were identified as requirement for testing, validation, simulation studies and operator training. These units form the heart of the plant and include all major process and utility systems. Despite this reduced fit-for-purpose modeling scope the Pearl GTL MPDS is still one of the largest simulators in the world. [Pg.162]

Entities participating in ITS and sharing information will have to comply with a number of standards concerning communication interfaces and how to interact. In Europe ETSI has defined a reference architecture for an ITS-Station [3]. One of the purposes with this standard is to define a common data model of information that can be shared among the ITS-Stations. All stations have local sensors that collect information about their vicinity which gives them a local perspective. This information is then shared among the participants to achieve global awareness. [Pg.6]

We need to point out that, if the wavelengths of laser radiation are less than the size of typical structures on the optical element, the Fresnel model gives a satisfactory approximation for the diffraction of the wave on a flat optical element If we have to work with super-high resolution e-beam generators when the size of a typical structure on the element is less than the wavelengths, in principle, we need to use the Maxwell equations. Now, the calculation of direct problems of diffraction, using the Maxwell equations, are used only in cases when the element has special symmetry (for example circular symmetry). As a rule, the purpose of this calculation in this case is to define the boundary of the Fresnel model approximation. In common cases, the calculation of the diffraction using the Maxwell equation is an extremely complicated problem, even if we use a super computer. [Pg.265]

For purposes of data correlation, model studies, and scale-up, it is useful to arrange variables into dimensionless groups. Table 6-7 lists many of the dimensionless groups commonly founa in fluid mechanics problems, along with their physical interpretations and areas of application. More extensive tabulations may oe found in Catchpole and Fulford (Ind. Eng. Chem., 58[3], 46-60 [1966]) and Fulford and Catchpole (Ind. Eng. Chem., 60[3], 71-78 [1968]). [Pg.674]

The purpose of this report is to bring the author s model and theory for carbon black reinforcement of rubbers to a conclusion, with additional experiments and discussion. This research consists of three papers (Part 1, Part 2, and Part 3), where the reinforcement of elastomers is generalized with the universal and common concept. Now, preceding the detailed discussion, we would like to discuss the previous concept generally accepted for carbon black reinforcement of rubbers and the author s new model and theory. [Pg.519]


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See also in sourсe #XX -- [ Pg.68 ]

See also in sourсe #XX -- [ Pg.68 ]




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Model purpose

Purpose common

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