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Problems and Directions

The main problem with the description as stated is that there are different kinds of axioms, yet there is insufficient mathematical theory (at least known to the author) to differentiate types of axioms. At present, a distinction should be made between bottom-up and top-down axioms. As mentioned earlier, if God would say that there are x halting programs of size n, a programmer could determine which ones they were by running all of them simultaneously until x of them halt. This kind of axiom, a top-down axiom, requires prior knowledge of the entire spectrum of the problem to determine. Another kind of axiom, a bottom-up axiom, requires a minimum of understanding in order to be apprehended. Its truth is knowable even if not provable within its own formalism, and its application is not intrinsically bounded. [Pg.115]

Are there other properties of axioms which are important to the sequence in [Pg.115]

Are there other prerequisites for finding these axioms  [Pg.115]

In what ways (if any) do axioms relate to program size  [Pg.115]

Using Turing Oracles in Cognitive Models of Problem-Solving [Pg.116]


Statistical concepts in many quality systems provide the basis for identifying the source of problems and directing improvement ef-... [Pg.33]

It is our goal in this book to address the problems, introduced earlier, that arise in a general data reconciliation problem. It is the culmination of several years of research and implementation of data reconciliation aspects in Argentina, the United States, and Australia. It is designed to provide a simple, smooth, and readable account of all aspects involved in data classification and reconciliation, while providing the interested reader with material, problems, and directions for further study. [Pg.25]

The theoretical studies undertaken over the last decade have led to significant breakthroughs in our understanding of tribology. However, much work remains to be done. In concluding, we would like to emphasize some of the important lessons learned, unresolved problems, and directions for future studies. [Pg.264]

In some cases it is possible to directly polycondense acid and phenols evolving water at about 300 C [41]. This process works well when catalysed with compoimds of group IV or V metals tin salts are preferred, especially dialkyl tin dialkanoates or oxides. The process is not really suitable if p-hydroxybenzoic acid is involved because this can imdergo decarboxylation at >200 "C. The polymerisation is not affected because the phenol formed volatilises at the high temperatures involved, but the resultant polyester will contain less than the anticipated mole ratio of hydroxybenzoate-derived units. Hydroxynaphthoic acid does not suffer from this problem, and direct esterification processes may be used if non-benzoate copolymers are required [42]. [Pg.9]

We decided to offer a collection of problems in this book as problems may stimulate further interest in the topics discussed in this book. Science books without figures tend to be unnecessarily tedious, and science books without problems tend to be unnecessarily stagnant. Our problems are of two kinds (i) They may broaden the topics considered and strengthen one s interest in continuing to explore particular topics further, and (ii) they may challenge some readers to try to solve some important problems and directly contribute to the advancement of the current science of structural chemistry, which has a number of open pending problems. [Pg.16]

Let us assume that stress gradient in axial direction is present but smooth. Then we can use a perturbation method and expand the solution of equation (30) in a series. The first term of this expansion will be a solution of the plane strain problem and potential N will be equal to zero. The next terms of the stress components will contain potential N also. [Pg.138]

As a first step in the direction outlined here some manufacturers and BAM last year discussed the problems and the possible procedures of such a system of quality assurance. As a result of this meeting round robin tests for the harmonization of the measurements of film system parameters and a possible procedure of surveillance of the quality of film systems were proposed. Closely related to these the BAM offers to perform the classification of film systems. But as during the production of films variations of the properties of the different batches cannot be avoided, the results of measurements of films of a single batch will be restricted to this charge, while only the measurements and mean of several batches of a film type will give representative values of its properties. This fact is taken into account already in section 4 of the standard EN 584-1 which can be interpreted as a kind of continuous surveillance. In accordance with this standard a film system caimot be certified on the base of measurements of a single emulsion only. [Pg.553]

We begin the mathematical analysis of the model, by considering the forces acting on one of the beads. If the sample is subject to stress in only one direction, it is sufficient to set up a one-dimensional problem and examine the components of force, velocity, and displacement in the direction of the stress. We assume this to be the z direction. The subchains and their associated beads and springs are indexed from 1 to N we focus attention on the ith. The absolute coordinates of the beads do not concern us, only their displacements. [Pg.185]

We would like to stress at this point that the derivation of (1.36) and (1.38)-(1.39) is connected with the simulation of contact problems and therefore contains some assumptions of a mechanical character. This remark is concerned with the sign of the function p in the problem (1.36) and with the direction of the vector pi,P2,p) in the problem (1.38), (1.39). Note that the classical approach to contact problems is characterized by a given contact set (Galin, 1980 Kikuchi, Oden, 1988 Grigolyuk, Tolkachev, 1980). In contact problems considered in the book, the contact set is unknown, and we obtain the so called free boundary problems. Other free boundary problems can be found in (Hoffmann, Sprekels, 1990 Elliot, Ock-endon, 1982 Antontsev et ah, 1990 Kinderlehrer et ah, 1979 Antontsev et ah, 1992 Plotnikov, 1995). [Pg.15]

Elliptic Equations Elhptic equations can be solved with both finite difference and finite element methods. One-dimensional elhptic problems are two-point boundary value problems. Two- and three-dimensional elliptic problems are often solved with iterative methods when the finite difference method is used and direct methods when the finite element method is used. So there are two aspects to consider howthe equations are discretized to form sets of algebraic equations and howthe algebraic equations are then solved. [Pg.480]

Turbine-Blade Cooling The turbine inlet temperatures of gas turbines have increased considerably over the past years and will continue to do so. This trend has been made possible by advancement in materials and technology, and the use of advanced turbine bladecooling techniques. The olade metal temperature must be kept below 1400° F (760° C) to avoid hot corrosion problems. To achieve this cooling air is bled from the compressor and is directed to the stator, the rotor, and other parts of the turbine rotor and casing to provide adequate cooling. The effect of the coolant on the aerodynamic, and thermodynamics depends on the type of cooling involved, the temperature of the coolant compared to the mainstream temperature, the location and direction of coolant injection, and the amount of coolant. [Pg.2511]


See other pages where Problems and Directions is mentioned: [Pg.20]    [Pg.311]    [Pg.170]    [Pg.203]    [Pg.308]    [Pg.282]    [Pg.115]    [Pg.115]    [Pg.20]    [Pg.311]    [Pg.170]    [Pg.203]    [Pg.308]    [Pg.282]    [Pg.115]    [Pg.115]    [Pg.268]    [Pg.723]    [Pg.2309]    [Pg.251]    [Pg.770]    [Pg.442]    [Pg.51]    [Pg.155]    [Pg.239]    [Pg.262]    [Pg.71]    [Pg.401]    [Pg.426]    [Pg.47]    [Pg.390]    [Pg.30]    [Pg.63]    [Pg.79]    [Pg.111]    [Pg.68]    [Pg.84]    [Pg.435]    [Pg.203]    [Pg.334]    [Pg.523]    [Pg.394]    [Pg.41]    [Pg.1440]    [Pg.2188]   


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Current problems and new directions

Open Problems and Future Directions

Potential Problems, and Future Directions

The Direct and Inverse Problem

Unsolved Problems and Future Directions

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