Predicting the Outcomes

The reservoir model will usually be a computer based simulation model, such as the 3D model described in Section 8. As production continues, the monitoring programme generates a data base containing information on the performance of the field. The reservoir model is used to check whether the initial assumptions and description of the reservoir were correct. Where inconsistencies between the predicted and observed behaviour occur, the model is reviewed and adjusted until a new match (a so-called history match ) is achieved. The updated model is then used to predict future performance of the field, and as such is a very useful tool for generating production forecasts. In addition, the model is used to predict the outcome of alternative future development plans. The criterion used for selection is typically profitability (or any other stated objective of the operating company). 

This is a question of reaction prediction. In fact, this is a deterministic system. If we knew the rules of chemistry completely, and understood chemical reactivity fully, we should be able to answer this question and to predict the outcome of a reaction. Thus, we might use quantum mechanical calculations for exploring the structure and energetics of various transition states in order to find out which reaction pathway is followed. This requires calculations of quite a high degree of sophistication. In addition, modeling the influence of solvents on... 

Numerical simulations are designed to solve, for the material body in question, the system of equations expressing the fundamental laws of physics to which the dynamic response of the body must conform. The detail provided by such first-principles solutions can often be used to develop simplified methods for predicting the outcome of physical processes. These simplified analytic techniques have the virtue of calculational efficiency and are, therefore, preferable to numerical simulations for parameter sensitivity studies. Typically, rather restrictive assumptions are made on the bounds of material response in order to simplify the problem and make it tractable to analytic methods of solution. Thus, analytic methods lack the generality of numerical simulations and care must be taken to apply them only to problems where the assumptions on which they are based will be valid. 

The solubility rules in Table 1.1 are used to predict the outcomes of precipitation reactions. 

Predict the outcome of neutralization reactions and write their chemical equations (Self-Test J.2). 

SOLUTION Compression increases the pressure but cooling lowers the pressure, and so it is not easy to predict the outcome without doing a calculation. Follow the procedure set out in Toolbox 4.1. 

EXAMPLE 17.2 Predicting the outcome of electron capture and positron emission... 

Published clinical scenarios outline the available options in making these decisions [36], It is impossible to predict the outcome of a future anaphylaxis episode with certainty based on the history of a previous episode [37]. Therefore, when in doubt, erring on the side of caution is generally advised prescribe one or more epinephrine autoinjectors, and advise the person at risk or the caregiver of a child at risk to inject epinephrine promptly in an anaphylaxis episode [36]. 

The concise Oxford dictionary of current English defines a model as a simplified. . . description of a system etc., to assist calculations and predictions. One can apply this definition in its wider sense to any intellectual activity (or its product) that tries to make out the components of a system and to predict the outcome of their interaction. Thus, to think is to model (beware, though, that the reverse is not necessarily true). 

These detailed cell models can be used to study the development in time of processes like myocardial ischaemia (a reduction in coronary blood flow that causes under-supply of oxygen to the cardiac muscle), or effects of genetic mutations on cellular electrophysiology. They allow to predict the outcome of changes in the cell s environment, and may even be used to assess drug actions. 

A metal will transfer electrons to any cation that is lower on the list. Furthermore, the list is in order of reactivity, so the greater the separation between the species, the more vigorous the reaction. Example shows how to use the activity series to predict the outcome of a metal displacement reaction. 

Weak acids and bases can be better assessed if the shapes of the flux-pH profiles were considered, as far as predicting the outcome of a particular choice of assay pH. 

Predicting the outcome of the reactions between LE chalcogen-donor molecules and di- and inter-halogens is still a challenge, and attempts have been made in this direction by judging whether all the different products could be formed from a common intermediate species following a general pattern of reactivity. In particular, S. Husebye proposed that this species was the [LE-X]4... 

The decision to market the product in liquid or powder form is often dictated by how stable the protein is in solution. This, in turn, must be determined experimentally, as there is no way to predict the outcome for any particular protein. Some proteins may remain stable for months (or even years) in solution, particularly if stabilizing excipients are added and the solution is refrigerated. Other proteins, particularly when purified, may retain biological activity for only a matter of hours or days when in aqueous solution. 

The results of such experiments, carried out over a range of temperatures, are summarized on a phase diagram (Fig. 4.1 b), which can be used to predict the outcome of any preparation in the NaF-ZnF2 system. In such diagrams, each phase is drawn as a line, as in the example of NaZnF3 above, because they show no composition range. Such compounds are referred to as stoichiometric compounds and, sometimes, with the appearance of the phase diagram in mind, line phases. 

Addy Press s book, Theoretical and Physical Principles of Organic Reactivity, Wiley, New York, 1995, is an invaluable tool for understanding the way constructing a reaction profile can help the physical chemist to predict the outcome of a chemical reaction. Lowry and Richardson s Mechanism and Theory in Organic Chemistry (above) is also germane. 

Although it is difficult to predict the outcome of restoration measures, this challenge must be tackled. Restoration measures considerably affect the hydromorphological... 

With a knowledge of pATa values, or a rough idea of relative values, one can predict the outcome of acid-base interactions. This may form an essential preliminary to many reactions, or provide us with an understanding of whether a compound is ionized... 

Predicting the outcome of electrophilic additions to alkynes from an extension of alkene reactivity usually works well, and can be applied to halogenations and hydrations. Hydration of an alkyne has a subtle twist, however the product is a ketone This can still be rationalized quite readily, though. 

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