Dependence concepts

Wolters, K. (2008, May). Formalisms, simulation, and potentials of a dependability concept for optimized system utilization pn German], Dr.-Ing. thesis. Chair of Dynamics and Control (SRS), Engineering Faculty, University of Duisburg-Essen, Duisburg, Germany. 

It has been previously outlined that the thermal stability of organic materials is a time-temperature dependent concept. Thus, heat-resistant adhesives are those that can be safely used for thousands of hours between 200 and 300°C. This definition excludes the epoxy and epoxy-phenolic adhesives which are, however, the predominant classes of polymers used in aeronautics. Epoxy adhesives based on... 

The principle of constraint satisfaction requires that tlie constraint set be satisfied before any state change can take place. It is tlierefore necessaiy tliat tlie constraining information be already present in the system. This information must be stored in other concepts, since data may be stored nowhere else tliese concepts must tlierefore stand as prerequisites to tlie concept being constrained and hence be logically connected to it. Constraints therefore fonn the interconnection between concepts. Since the constraints allow legitimate data values from prerequisite concepts to be used in the dependent concept, constraints also define data flows within the system, though only valid data can traverse the flow line. This contrasts with most taflow diagrams, where there is little or no definition of what data traverses which flow line and under what conditions. 

Seamless dependability / trust concept up to SW and system efficient integration of the computing platform dedicated mechanisms into the overall dependability concept of the system... 

As is described in the previous section, the flexibility in selecting the inlet and outlet temperatures is a unique characteristic of the Super LWR core. It is also expected that raising the core outlet temperature above the pseudocritical temperature will make the Super LWR a more attractive concept. Hereafter, this chapter focuses on the core design of the average temperature target-dependent concept, but the other two concepts are also briefly introduced. 

Figure 1 Mesoscales in multiphase reactors a level-dependent concept.

The detectability of critical defects with CT depends on the final image quality and the skill of the operator, see figure 2. The basic concepts of image quality are resolution, contrast, and noise. Image quality are generally described by the signal-to-noise ratio SNR), the modulation transfer function (MTF) and the noise power spectrum (NFS). SNR is the quotient of a signal and its variance, MTF describes the contrast as a function of spatial frequency and NFS in turn describes the noise power at various spatial frequencies [1, 3]. 

The idea that unsymmetrical molecules will orient at an interface is now so well accepted that it hardly needs to be argued, but it is of interest to outline some of the history of the concept. Hardy [74] and Harkins [75] devoted a good deal of attention to the idea of force fields around molecules, more or less intense depending on the polarity and specific details of the structure. Orientation was treated in terms of a principle of least abrupt change in force fields, that is, that molecules should be oriented at an interface so as to provide the most gradual transition from one phase to the other. If we read interaction energy instead of force field, the principle could be reworded on the very reasonable basis that molecules will be oriented so that their mutual interaction energy will be a maximum. 

It must be kept in mind that both pictures are modelistic and invoke extrather-modynamic concepts. Except mathematically, there is no such thing as a two-dimensional gas, and the solution whose osmotic pressure is calculated is not uniform in composition, and its average concentration depends on the depth assumed for the surface layer. 

It will be seen that each method for surface area determination involves the measurement of some property that is observed qualitatively to depend on the extent of surface development and that can be related by means of theory to the actual surface area. It is important to realize that the results obtained by different methods differ, and that one should in general expect them to differ. The problem is that the concept of surface area turns out to be a rather elusive one as soon as it is examined in detail. 

Modem photochemistry (IR, UV or VIS) is induced by coherent or incoherent radiative excitation processes [4, 5, 6 and 7]. The first step within a photochemical process is of course a preparation step within our conceptual framework, in which time-dependent states are generated that possibly show IVR. In an ideal scenario, energy from a laser would be deposited in a spatially localized, large amplitude vibrational motion of the reacting molecular system, which would then possibly lead to the cleavage of selected chemical bonds. This is basically the central idea behind the concepts for a mode selective chemistry , introduced in the late 1970s [127], and has continuously received much attention [10, 117. 122. 128. 129. 130. 131. 132. 133. 134... 

When constructing more general molecular wave functions there are several concepts that need to be defined. The concept of geometry is inhoduced to mean a (time-dependent) point in the generalized phase space for the total number of centers used to describe the END wave function. The notations R and P are used for the position and conjugate momenta vectors, such that... 

Obviously, to model these effects simultaneously becomes a very complex task. Hence, most calculation methods treat the effects which are not directly related to the molecular structure as constant. As an important consequence, prediction models are valid only for the system under investigation. A model for the prediction of the acidity constant pfQ in aqueous solutions cannot be applied to the prediction of pKj values in DMSO solutions. Nevertheless, relationships between different systems might also be quantified. Here, Kamlet s concept of solvatochro-mism, which allows the prediction of solvent-dependent properties with respect to both solute and solvent [1], comes to mind. 

Molecular mechanics depends on the concept of atom types and parameters associated with these atom types. Since the number of atom types is very large for the universe of possible molecules, parameters will probably be missing for a random new molecule unless a force field has been developed for molecules similar to the new molecule. Molecular mechanics predicts how the new molecule will behave based upon the behavior of known, similar molecules. 

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