Author: T. V. Griffiths
Publisher:
ISBN:
Category : Algorithms
Languages : en
Pages : 22
Book Description
A number of diverse recognition procedures that have been proposed for parsing sentences with respect to a context-free grammar are described in this paper by means of a common device. Each procedure is defined by giving an algorithm for obtaining a nondeterministic Turing Machine recognizer that is equivalent to a given context-free grammar. The formalization of the Turing Machine has been chosen to make possible particularly simple descriptions of the parsing procedures considered.
On the Relative Efficiencies of Context-free Grammar Recognizers
Author: T. V. Griffiths
Publisher:
ISBN:
Category : Algorithms
Languages : en
Pages : 22
Book Description
A number of diverse recognition procedures that have been proposed for parsing sentences with respect to a context-free grammar are described in this paper by means of a common device. Each procedure is defined by giving an algorithm for obtaining a nondeterministic Turing Machine recognizer that is equivalent to a given context-free grammar. The formalization of the Turing Machine has been chosen to make possible particularly simple descriptions of the parsing procedures considered.
Publisher:
ISBN:
Category : Algorithms
Languages : en
Pages : 22
Book Description
A number of diverse recognition procedures that have been proposed for parsing sentences with respect to a context-free grammar are described in this paper by means of a common device. Each procedure is defined by giving an algorithm for obtaining a nondeterministic Turing Machine recognizer that is equivalent to a given context-free grammar. The formalization of the Turing Machine has been chosen to make possible particularly simple descriptions of the parsing procedures considered.
On the Relative Efficiencies of Context-free Grammar Recognizers
Author: Thomas V. Griffiths
Publisher:
ISBN:
Category : Algorithms
Languages : en
Pages : 0
Book Description
A number of diverse recognition procedures that have been proposed for parsing sentences with respect to a context-free grammar are described in this paper by means of a common device. Each procedure is defined by giving an algorithm for obtaining a nondeterministic Turing Machine recognizer that is equivalent to a given context-free grammar. The formalization of the Turing Machine has been chosen to make possible particularly simple descriptions of the parsing procedures considered.
Publisher:
ISBN:
Category : Algorithms
Languages : en
Pages : 0
Book Description
A number of diverse recognition procedures that have been proposed for parsing sentences with respect to a context-free grammar are described in this paper by means of a common device. Each procedure is defined by giving an algorithm for obtaining a nondeterministic Turing Machine recognizer that is equivalent to a given context-free grammar. The formalization of the Turing Machine has been chosen to make possible particularly simple descriptions of the parsing procedures considered.
The Spectral Shifts of Truncated Sinusoids
Author: Kurt Toman
Publisher:
ISBN:
Category : Radio waves
Languages : en
Pages : 12
Book Description
Publisher:
ISBN:
Category : Radio waves
Languages : en
Pages : 12
Book Description
Production of H− (1s2) by Hydrogen Atom Collisions
Author: R. A. Mapleton
Publisher:
ISBN:
Category : Collisional excitation
Languages : en
Pages : 16
Book Description
The prior and post Born matrix elements are used to calculate the cross sections for H( - )(1s2) production in hydrogen atom collisions. In contrast to the original version of this work done by Mapleton in 1960, the plane wave approximation to the Coulomb function is partially corrected. The same H( - ) wave functions are used, and the post cross sections are substantially unaltered. Cross sections calculated with the improved H( - ) wave function as compared with the other H( - ) wave functions are from twenty to thirty-five per cent larger for the prior case and twenty to thirty per cent larger for the post case. The post-prior discrepancy, expressed as a ratio, varies between 0.001 and 0.33. (Author).
Publisher:
ISBN:
Category : Collisional excitation
Languages : en
Pages : 16
Book Description
The prior and post Born matrix elements are used to calculate the cross sections for H( - )(1s2) production in hydrogen atom collisions. In contrast to the original version of this work done by Mapleton in 1960, the plane wave approximation to the Coulomb function is partially corrected. The same H( - ) wave functions are used, and the post cross sections are substantially unaltered. Cross sections calculated with the improved H( - ) wave function as compared with the other H( - ) wave functions are from twenty to thirty-five per cent larger for the prior case and twenty to thirty per cent larger for the post case. The post-prior discrepancy, expressed as a ratio, varies between 0.001 and 0.33. (Author).
Matrix Criteria for Arbitrary Reliability in Iterated Neural Nets
Author: Rocco H. Urbano
Publisher:
ISBN:
Category : Iterative methods (Mathematics)
Languages : en
Pages : 12
Book Description
In a previous paper by this author, the problem of achieving arbitrary reliability for combinatorial nets from arbitrarily unreliable elements was reduced to the study of convergence properties of an associated polynomial system. In this paper simple criteria which specify the convergence of such a system to a nodal fixed point are obtained from known results in matrix theory. (Convergence to a nodal point implies that the corresponding net approaches reliability arbitrarily near 1 for a particular function.) Theorems are also given which show that it is possible to obtain from a single system converging to a nodal fixed point, many systems having this property.
Publisher:
ISBN:
Category : Iterative methods (Mathematics)
Languages : en
Pages : 12
Book Description
In a previous paper by this author, the problem of achieving arbitrary reliability for combinatorial nets from arbitrarily unreliable elements was reduced to the study of convergence properties of an associated polynomial system. In this paper simple criteria which specify the convergence of such a system to a nodal fixed point are obtained from known results in matrix theory. (Convergence to a nodal point implies that the corresponding net approaches reliability arbitrarily near 1 for a particular function.) Theorems are also given which show that it is possible to obtain from a single system converging to a nodal fixed point, many systems having this property.
A Study of the Nighttime Ionosphere and Its Reaction Rates
Author: William Swider (Jr.)
Publisher:
ISBN:
Category : Chemical reactions
Languages : en
Pages : 26
Book Description
Publisher:
ISBN:
Category : Chemical reactions
Languages : en
Pages : 26
Book Description
Expansion of Initial High-current Spark Channels
Author: Heinz Fischer
Publisher:
ISBN:
Category : Electric spark
Languages : en
Pages : 16
Book Description
Publisher:
ISBN:
Category : Electric spark
Languages : en
Pages : 16
Book Description
Electrophoretic Power Generation in Thermally Ionized Plasmas
Author: C. C. Leiby (Jr.)
Publisher:
ISBN:
Category : Electrophoresis
Languages : en
Pages : 42
Book Description
Druyvesteyn's solutions for electrophoretically induced gas flows in electrical discharges in gases were extended over a larger pressure range and corrected for the influence of Debye shielding effects. The effects of molecular or 'slip' flow were also taken into account. These more accurate and general solutions were applied to the reverse phenomenon of space charge field generation arising from the flow of a thermally ionized cesium plasma through a tube. Under such flow conditions, a non-linear differential equation for the axial pressure distribution was obtained but not solved. However, it was possible to obtain estimates of the ranges of cesium pressure, temperature and tube radii which would be required for sensible levels of electric power generation. Anaphoretic flow power levels of the order of 0.1 to 10 watts, in tubes of laboratory dimensions (radii of 10 cm or less), appear feasible at temperatures from 1700 to 2400K. Sensible power generation levels at lower temperatures require very large diameter tubes, and therefore are not feasible. (Author).
Publisher:
ISBN:
Category : Electrophoresis
Languages : en
Pages : 42
Book Description
Druyvesteyn's solutions for electrophoretically induced gas flows in electrical discharges in gases were extended over a larger pressure range and corrected for the influence of Debye shielding effects. The effects of molecular or 'slip' flow were also taken into account. These more accurate and general solutions were applied to the reverse phenomenon of space charge field generation arising from the flow of a thermally ionized cesium plasma through a tube. Under such flow conditions, a non-linear differential equation for the axial pressure distribution was obtained but not solved. However, it was possible to obtain estimates of the ranges of cesium pressure, temperature and tube radii which would be required for sensible levels of electric power generation. Anaphoretic flow power levels of the order of 0.1 to 10 watts, in tubes of laboratory dimensions (radii of 10 cm or less), appear feasible at temperatures from 1700 to 2400K. Sensible power generation levels at lower temperatures require very large diameter tubes, and therefore are not feasible. (Author).
On the Acoustic Basis of the Perception of Intonation by Linguists
Author: Philip Lieberman
Publisher:
ISBN:
Category : Intonation (Phonetics)
Languages : en
Pages : 26
Book Description
Publisher:
ISBN:
Category : Intonation (Phonetics)
Languages : en
Pages : 26
Book Description
Measurement Techniques in Clouds
Author: Donald R. Fitzgerald
Publisher:
ISBN:
Category : Atmospheric electricity
Languages : en
Pages : 28
Book Description
Publisher:
ISBN:
Category : Atmospheric electricity
Languages : en
Pages : 28
Book Description