Interpretive description

The focus of social constructivists on the necessarily interpretative descriptions, or accounts, of an artefact made by different social groups means the reality of the artefact itself tends to be lost. However, when social constructivists emphasize the... 

The variety of VB wavefunctions incorporating multiple orbital products is enormous and next to impossible to arrange within a formal classification scheme as most of these do not emerge as the result of more or less systematic attempts to improve a given reference as common in MO theory, but as specific constructions aimed to achieve an economic and easy-to-interpret description of a particular problem. 

Modeling, however, is the anticipation, interpretation, description and then simulation of the course of these processes over time. This is all carried out using the information we have about the system being studied information about the nature and concentration of the present species, the nature and location of the phases, parameters such as temperature and partial gas pressure. Generally, the model of a process can also be expressed by a number of equations that relate these parameters to each other over time. To obtain these relations, the entire process has to be clearly described. If the simirlation and experimental results are compatible, the model will be validated, allowing us to interpret the observed phenomena. 

Availability of a representative set of data examples. Such a set may significantly simplify construction of any automatic interpretation system. The example data is usually obtained from calibration pieces, however, they usually represent only the most common defects and are usually expensive to manufacture. Recently more and more data is stored as digital inspection records, unfortunately the stored data is rarely fully classified, as this would increase the cost of inspection (usually only the serious defects are given full description in the reports). 

In practice, each CSF is a Slater determinant of molecular orbitals, which are divided into three types inactive (doubly occupied), virtual (unoccupied), and active (variable occupancy). The active orbitals are used to build up the various CSFs, and so introduce flexibility into the wave function by including configurations that can describe different situations. Approximate electronic-state wave functions are then provided by the eigenfunctions of the electronic Flamiltonian in the CSF basis. This contrasts to standard FIF theory in which only a single determinant is used, without active orbitals. The use of CSFs, gives the MCSCF wave function a structure that can be interpreted using chemical pictures of electronic configurations [229]. An interpretation in terms of valence bond sti uctures has also been developed, which is very useful for description of a chemical process (see the appendix in [230] and references cited therein). 

The preferable theoretical tools for the description of dynamical processes in systems of a few atoms are certainly quantum mechanical calculations. There is a large arsenal of powerful, well established methods for quantum mechanical computations of processes such as photoexcitation, photodissociation, inelastic scattering and reactive collisions for systems having, in the present state-of-the-art, up to three or four atoms, typically. " Both time-dependent and time-independent numerically exact algorithms are available for many of the processes, so in cases where potential surfaces of good accuracy are available, excellent quantitative agreement with experiment is generally obtained. In addition to the full quantum-mechanical methods, sophisticated semiclassical approximations have been developed that for many cases are essentially of near-quantitative accuracy and certainly at a level sufficient for the interpretation of most experiments.These methods also are com-... 

A familiar feature of the electronic theory is the classification of substituents, in terms of the inductive and conjugative or resonance effects, which it provides. Examples from substituents discussed in this book are given in table 7.2. The effects upon orientation and reactivity indicated are only the dominant ones, and one of our tasks is to examine in closer detail how descriptions of substituent effects of this kind meet the facts of nitration. In general, such descriptions find wide acceptance, the more so since they are now known to correspond to parallel descriptions in terms of molecular orbital theory ( 7.2.2, 7.2.3). Only in respect of the interpretation to be placed upon the inductive effect is there still serious disagreement. It will be seen that recent results of nitration studies have produced evidence on this point ( 9.1.1). 

Hughes and Ingold interpreted second order kinetic behavior to mean that the rate determining step is bimolecular that is that both hydroxide ion and methyl bromide are involved at the transition state The symbol given to the detailed description of the mech anism that they developed is 8 2 standing for substitution nucleophilic bimolecular... 

Definiteness. Adequate description or definiteness requites that the patent claims provide an outline of those elements which are integral to the appHcation s invention. In turn, the specification acts as a dictionary wherein the reader can interpret and understand the elements in the patent claims. Complementary to the requirement of definiteness is the requirement that the appHcation must disclose the entire invention. The appHcant cannot make a claim of right to the invention where essential elements of the invention are not disclosed in the patent. 

A scientific basis for the evaluation and interpretation of data is contained in the accompanying table descriptions. These tables characterize the way in which sample values will vary by chance alone in the context of individual obsei vations, averages, and variances. 

More detailea descriptions of small-scale sedimentation and filtration tests are presented in other parts of this section. Interpretation of the results and their conversion into preliminary estimates of such quantities as thickener size, centrifuge capacity, filter area, sludge density, cake diyness, and wash requirements also are discussed. Both the tests and the data treatment must be in experienced hands if error is to be avoided. 

Motivation Unit tests require a substantial investment in time and resources to complete successfully. This is the case whether the test is a straightforward analysis of pump performance or a complex analysis of an integrated reactor and separation train. The uncertainties in the measurements, the likelihood that different underlying problems lead to the same symptoms, and the multiple interpretations of unit performance are barriers against accurate understanding of the unit operation. The goal of any unit test should be to maximize the success (i.e., to describe accurately unit performance) while minimizing the resources necessary to arrive at the description and the subsequent recommendations. The number of measurements and the number of trials should be selected so that they are minimized. 

When the number of measurement sets is substantially less than that indicated Fig. 30-25, the interpretation becomes problematic. One option is to use the parameter v ues from one period to describe the measurements from another. If the description is within measurement error, the operation has not changed. If there is a substantial difference between the predictions and the measurements, it is hkely that the operation has changed. Methods such as those developed by Narasimhan et al. (1986) can be used when the number of measurements are large. When implementing automatic methods to treat a large number of measurements, analysts should ensure that the unit is at steady state for each time period. 

We will attempt to address a number of these phenomena in terms of their micromechanical origins, and to give the essential quantitative ideas that connect the macroscale (continuum description) with the microscale. We also will discuss the importance of direct observations, wherever possible, in establishing uniqueness of scientific interpretation. 

Computer simulation can be used to provide a stepping stone between experiment and the simplified analytical descriptions of the physical behavior of biological systems. But before gaining the right to do this, we must first validate a simulation by direct comparison with experiment. To do this we must compare physical quantities that are measurable or derivable from measurements with the same quantities derived from simulation. If the quantities agree, we then have some justification for using the detailed information present in the simulation to interpret the experiments. 

Several methods of quantitative description of molecular structure based on the concepts of valence bond theory have been developed. These methods employ orbitals similar to localized valence bond orbitals, but permitting modest delocalization. These orbitals allow many fewer structures to be considered and remove the need for incorporating many ionic structures, in agreement with chemical intuition. To date, these methods have not been as widely applied in organic chemistry as MO calculations. They have, however, been successfully applied to fundamental structural issues. For example, successful quantitative treatments of the structure and energy of benzene and its heterocyclic analogs have been developed. It remains to be seen whether computations based on DFT and modem valence bond theory will come to rival the widely used MO programs in analysis and interpretation of stmcture and reactivity. 

Both the language of valence bond theory and of molecular orbital theory are used in discussing structural effects on reactivity and mechanism. Our intent is to illustrate both approaches to interpretation. A decade has passed since the publication of the Third Edition. That decade has seen significant developments in areas covered by the text. Perhaps most noteworthy has been the application of computational methods to a much wider range of problems of structure and mechanism. We have updated the description of computational methods and have included examples throughout the text of application of computational methods to specific reactions. 

Historically, the problems studied and the approaches followed in scientific investigations are strongly constrained by the loading methods and diagnostics available to a particular investigator. Hence, the complete scientific description of shock-compressed matter often requires the interpretation of experiments from a number of independent directions that are often not consistent with each other and may contain significant ambiguities. 

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