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Mathematical Example

Now, in the Posterior Analytics, Aristode s mathematical examples all concern some particular genus a mathematician may study and not mathematics itself. Nonetheless, the terminology Aristode uses when he characterizes mathematics itself is the same as his terminology in the Posterior Analytics. According to such a characterization, mathematicians study bodies but not qua mobile. So, if Aristodes use of the qua locution is consistent in both cases, he must have thought there are syllogisms of the following form. [Pg.17]

Table 2 shows which concentration of HCN in air can be rapidly fatal to humans. Naturally these values are not the results of experiments on humans, but projections based, for safety reasons, on the lower safety limit. To demonstrate a stout person weighing 100 kg (roughly 220 lbs.) must absorb approximately 100 mg HCN for this to be fatal. The respiration rate of a person at rest is about 15 liters of air per minute.85 Given a HCN concentration of 0.02%/vol. (approximately 0.24 mg/liter), the victim must breathe in about 416 liters of air before he has absorbed the fatal dose of HCN. At 15 liters per minute, this would take just under half an hour. If he has a robust constitution, he may survive even this exposure time. If, however, one postulates a sensitive person of only 50 kg body weight (approximately 110 lbs.), whose respiration rate has increased to 40 liters per minute due to hard work or excitement, then the fatal 208 liters of air will have been breathed in by this person within 5 minutes. These mathematical examples show that safety guidelines are always set in such a way as to protect even the smaller and weaker persons from harm under a kind of worst case scenario. Also, the specifications given in the literature, immediately and rapidly fataF, are so indefinite as to be unsatisfactory. [Pg.350]

We briefly review here several elements of vector analysis that are needed later for a better and more complete description the reader is referred to textbooks of mathematics. Examples of vectors are the position vector r — ix + jy + kz, where i, j, k are unit vectors that coincide with the mutually orthogonal x, y, z axes of the coordinate system, and x, y, z are the corresponding coordinates. A vector in this space is designated by A = i + 7 Ay + kA, where the Ax are the components of the A vector along the three axes. We will also need the gradient vector operator, defined by V =id/dx + 7 9/9y + kdjdz-The following vector manipulations are of relevance. [Pg.13]

We shall not refer here to the application of suitable mathematical examples to this equilibrium process, as these are dealt with in detail in textbooks of physical chemistry. The ester, which is present in the upper phase of the heterogeneous system formed, is hydrophobic and readily dissolves plastics, fats, resins and other high molecular mass organic substances. The process in which it is formed is reversed when it is treated with sodium hydroxide. [Pg.307]

Obtaining qualitative or quantitative values of intensive parameters based on the compositions of micas and the coexisting phases. Here the analogy with the mathematics example is rigorously exact and, as discussed previously, is a direct manifestation of the Gibbs Phase Rule. [Pg.423]

The type of balancing required is strictly dependent on the amount of current needed. In addition, how much cell-balancing current does on need to take care of an initial pack imbalanc e One should always look at it from a milliampere-hour requirement. The c ell-balancing concept can be clear if the following mathematical example of a 10 Ah battery pack capacity with 1 h charge is reviewed using the assumed values of certain parameters ... [Pg.364]

These problems provide a mathematical example of how the slope or y-intercept of a line can represent a physical phenomenon, in this case the rise in global temperature as CO2 concentration rises (°C per ppm). This opportunity can be used to talk about how the units for the slope are the units of the y-vaiiable per the units of the x-variable because of the nature of the formula for slope, as... [Pg.83]

Most constraints can be evaluated by scoping the problem with different boundaries, as illustrated in Example 6.2. If this approach cannot be applied, then mathematical programming must be used to obtain the energy target. ... [Pg.184]

The example of a binary mixture is used to demonstrate the increased complexity of the phase diagram through the introduction of a second component in the system. Typical reservoir fluids contain hundreds of components, which makes the laboratory measurement or mathematical prediction of the phase behaviour more complex still. However, the principles established above will be useful in understanding the differences in phase behaviour for the main types of hydrocarbon identified. [Pg.101]

Once the production potential of the producing wells is insufficient to maintain the plateau rate, the decline periodbegins. For an individual well in depletion drive, this commences as soon as production starts, and a plateau for the field can only be maintained by drilling more wells. Well performance during the decline period can be estimated by decline curve analysis which assumes that the decline can be described by a mathematical formula. Examples of this would be to assume an exponential decline with 10% decline per annum, or a straight line relationship between the cumulative oil production and the logarithm of the water cut. These assumptions become more robust when based on a fit to measured production data. [Pg.209]

The above example is a simple one, and it can be seen that the individual items form part of the chain in the production system, in which the items are dependent on each other. For example, the operating pressure and temperature of the separators will determine the inlet conditions for the export pump. System modelling may be performed to determine the impact of a change of conditions in one part of the process to the overall system performance. This involves linking together the mathematical simulation of the components, e.g. the reservoir simulation, tubing performance, process simulation, and pipeline behaviour programmes. In this way the dependencies can be modelled, and sensitivities can be performed as calculations prior to implementation. [Pg.342]

One feature of this inequality warrants special attention. In the previous paragraph it was shown that the precise measurement of A made possible when v is an eigenfiinction of A necessarily results in some uncertainty in a simultaneous measurement of B when the operators /land fido not conmuite. However, the mathematical statement of the uncertainty principle tells us that measurement of B is in fact completely uncertain one can say nothing at all about B apart from the fact that any and all values of B are equally probable A specific example is provided by associating A and B with the position and momentum of a particle moving along the v-axis. It is rather easy to demonstrate that [p, x]=- ih, so that If... [Pg.16]

A marvellous and rigorous treatment of non-relativistic quantum mechanics. Although best suited for readers with a fair degree of mathematical sophistication and a desire to understand the subject in great depth, the book contains all of the important ideas of the subject and many of the subtle details that are often missing from less advanced treatments. Unusual for a book of its type, highly detailed solutions are given for many illustrative example problems. [Pg.52]

In the example of the previous section, the release of the stop always leads to the motion of the piston in one direction, to a final state in which the pressures are equal, never in the other direction. This obvious experimental observation turns out to be related to a mathematical problem, the integrability of differentials in themiodynamics. The differential Dq, even is inexact, but in mathematics many such expressions can be converted into exact differentials with the aid of an integrating factor. [Pg.333]

Figure A3.13.2 illustrates the origin of these quantities. Refer to [47] for a detailed mathematical discussion as well as the treatment of radiative laser excitation, in which incubation phenomena are unportant. Also refer to [11] for some classical examples in thennal systems. Figure A3.13.2 illustrates the origin of these quantities. Refer to [47] for a detailed mathematical discussion as well as the treatment of radiative laser excitation, in which incubation phenomena are unportant. Also refer to [11] for some classical examples in thennal systems.
Atoms have complete spherical synnnetry, and the angidar momentum states can be considered as different synnnetry classes of that spherical symmetry. The nuclear framework of a molecule has a much lower synnnetry. Synnnetry operations for the molecule are transfonnations such as rotations about an axis, reflection in a plane, or inversion tlnough a point at the centre of the molecule, which leave the molecule in an equivalent configuration. Every molecule has one such operation, the identity operation, which just leaves the molecule alone. Many molecules have one or more additional operations. The set of operations for a molecule fonn a mathematical group, and the methods of group theory provide a way to classify electronic and vibrational states according to whatever symmetry does exist. That classification leads to selection rules for transitions between those states. A complete discussion of the methods is beyond the scope of this chapter, but we will consider a few illustrative examples. Additional details will also be found in section A 1.4 on molecular symmetry. [Pg.1134]

As an example for the mathematical treatment, we take the bimolecular reaction... [Pg.2121]

Phase factors of this type are employed, for example, by the Baer group [25,26]. While Eq. (34) is strictly applicable only in the immediate vicinity of the conical intersection, the continuity of the non-adiabatic coupling, discussed in Section HI, suggests that the integrated value of (x Vq x+) is independent of the size or shape of the encircling loop, provided that no other conical intersection is encountered. The mathematical assumption is that there exists some phase function, vl/(2), such that... [Pg.13]

To demonstrate the basic ideas of molecular dynamics calculations, we shall first examine its application to adiabatic systems. The theory of vibronic coupling and non-adiabatic effects will then be discussed to define the sorts of processes in which we are interested. The complications added to dynamics calculations by these effects will then be considered. Some details of the mathematical formalism are included in appendices. Finally, examples will be given of direct dynamics studies that show how well the systems of interest can at present be treated. [Pg.256]

Recent mathematical work suggests that—especially for nonlinear phenomena—certain geometric properties can be as important as accuracy and (linear) stability. It has long been known that the flows of Hamiltonian systems posess invariants and symmetries which describe the behavior of groups of nearby trajectories. Consider, for example, a two-dimensional Hamiltonian system such as the planar pendulum H = — cos(g)) or the... [Pg.350]

Redundant, isomorphic structures have to be eliminated by the computer before it produces a result. The determination of whether structures are isomorphic or not stems from a mathematical operation called permutation the structures are isomorphic if they can be interconverted by permutation (Eq. (6) see Section 2.8.7). The permutation P3 is identical to P2 if a mathematical operation (P ) is applied. This procedure is described in the example using atom 4 of P3 (compare Figure 2-40, third line). In permutation P3 atom 4 takes the place of atom 5 of the reference structure but place 5 in P2. To replace atom 4 in P2 at position 5, both have to be interchanged, which is expressed by writing the number 4 at the position of 5 in P. Applying this to all the other substituents, the result is a new permutation P which is identical to P]. [Pg.58]


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