Showing papers by "Carnegie Mellon University published in 1972"
Book•
01 Jun 1972TL;DR: The aim of the book is to advance the understanding of how humans think by putting forth a theory of human problem solving, along with a body of empirical evidence that permits assessment of the theory.
Abstract: : The aim of the book is to advance the understanding of how humans think. It seeks to do so by putting forth a theory of human problem solving, along with a body of empirical evidence that permits assessment of the theory. (Author)
10,770 citations
TL;DR: In this paper, the authors discuss modularization as a mechanism for improving the flexibility and comprehensibility of a system while allowing the shortening of its development time, and the effectiveness of modularization is dependent upon the criteria used in dividing the system into modules.
Abstract: This paper discusses modularization as a mechanism for improving the flexibility and comprehensibility of a system while allowing the shortening of its development time. The effectiveness of a “modularization” is dependent upon the criteria used in dividing the system into modules. A system design problem is presented and both a conventional and unconventional decomposition are described. It is shown that the unconventional decompositions have distinct advantages for the goals outlined. The criteria used in arriving at the decompositions are discussed. The unconventional decomposition, if implemented with the conventional assumption that a module consists of one or more subroutines, will be less efficient in most cases. An alternative approach to implementation which does not have this effect is sketched.
5,028 citations
TL;DR: In this article, the authors provide a simple example of an economy in which equilibrium prices and quantities exhibit what may be the central feature of the modern business cycle: a systematic relation between the rate of change in nominal prices and the level of real output.
4,451 citations
TL;DR: In this paper, it was shown that the strained cyclic molecules cyclopropene and cyclopsopropane are preferentially stabilized by the addition of d functions, and the relative energies were given to an accuracy of 3 kcal/mole or better.
955 citations
TL;DR: This theory was tested in four experiments in which S s were timed as they judged whether a sentence was true or false of a picture and it was shown that this theory is consistent with previous studies on sentence comprehension, sentence verification, concept verification, and other related phenomena.
951 citations
TL;DR: This paper presents an approach to writing specifications for parts of software systems sufficiently precise and complete that other pieces of software can be written to interact with the piece specified without additional information.
Abstract: This paper presents an approach to writing specifications for parts of software systems. The main goal is to provide specifications sufficiently precise and complete that other pieces of software can be written to interact with the piece specified without additional information. The secondary goal is to include in the specification no more information than necessary to meet the first goal. The technique is illustrated by means of a variety of examples from a tutorial system.
747 citations
647 citations
TL;DR: In nuclear magnetic resonance studies, designed to establish the alignment of the probes relative to the membrane lipids, it was found that the signal originating from the choline methyl protons of the membrane phospholipids is broadened by the spin probes; this effect was found to decrease as the paramagnetic ring is farther removed from the polar end of the fatty acid probe.
390 citations
TL;DR: In this paper, the authors analyzed the amount of information seeking by buyers of new cars and major household appliances and found that purchase behavior supports the hypothesis that consumers seek information seeking from new cars.
Abstract: National survey data on the amount of information seeking by buyers of new cars and major household appliances are analyzed by AID and MCA. The findings lend support to the hypothesis that purchase...
389 citations
TL;DR: The theory of simple materials was formulated by as discussed by the authors in 1958 in reference [N2] and has served as a foundation for a large part of the research in continuum physics since 1958, and considering that the concepts and even the notations of [N 2] are now used routinely and without reference in textbooks on continuum mechanics.
Abstract: The original theory of simple materials was formulated by me in 1958 in reference [N2]. I proposed this theory in an attempt to unify and clarify the confusing variety of theories of mechanical behavior of materials that had been proposed in the literature up to that time. One can perhaps say that the attempt was moderately successful, considering that this first theory of simple materials has served as a foundation for a large part of the research in continuum physics since 1958, and considering that the concepts and even the notations of [N2] are now used routinely and without reference in textbooks on continuum mechanics.
307 citations
05 Dec 1972
TL;DR: An overview of the goals, design, and status of this hardware/software complex, and some of the research problems raised and analytic problems solved in the course of its construction are described.
Abstract: In the Summer of 1971 a project was initiated at CMU to design the hardware and software for a multi-processor computer system using minicomputer processors (i.e., PDP-11's). This paper briefly describes an overview (only) of the goals, design, and status of this hardware/software complex, and indicates some of the research problems raised and analytic problems solved in the course of its construction.
TL;DR: In this article, the authors consider the following idealized description of an economy's behavior over time: In each period the labor force works with several different types of capital stocks to produce several types of output.
TL;DR: This article used a graph to show the interaction of asset markets, output markets, and the financing of the budget deficit, showing that both the size of deficits and the method of financing affect output and prices.
Abstract: vent output prices and output from adjusting instantaneously. Both the size of deficits and the method of financing affect output and prices. Some principal implications are derived. Several of these are also demonstrated, using a graph to show the interaction of asset markets, output markets, and the financing of the budget deficit. Some main implications of standard analysis are rejected. The basis for several "monetarist" conclusions is shown.
TL;DR: In this paper, molecular orbital calculations on methanediol have been used to predict the favored orientations and interatomic distances of the C-O-C-O R portion in pyranoses.
TL;DR: In this paper, a general theory is presented for determining the quasistatic Stokes resistance of a particle or an aggregate of particles of arbitrary shape which move with arbitrary translational and rotational velocities in an infinite viscous fluid subjected to a general linear shear flow in the absence of the particles.
TL;DR: The formal description of the synchronization mechanism makes it very easy to prove that the buffer will neither overflow nor underflow, that senders and receivers will never operate on the same message frame in the buffer nor will they run into a deadlock.
Abstract: Formalization of a well-defined synchronization mechanism can be used to prove that concurrently running processes of a system communicate correctly. This is demonstrated for a system consisting of many sending processes which deposit messages in a buffer and many receiving processes which remove messages from that buffer. The formal description of the synchronization mechanism makes it very easy to prove that the buffer will neither overflow nor underflow, that senders and receivers will never operate on the same message frame in the buffer nor will they run into a deadlock.
TL;DR: This paper studies the locally testable languages introduced by McNaughton and Papert by means of their syntactic semigroups and obtains wreath product and direct product decompositions for these semig groups.
TL;DR: In this paper, a systematic procedure for improving the basis set and refining the equilibrium geometry of the cations CH + 3, CH + 5, C 2 H + 3 and C 2H + 5 is presented.
TL;DR: In this paper, the mathematical theory of voting was used to shed light on traditional rules of parliamentary procedure, such as the division of the question on amendments, which affects the creation of successful packages.
Abstract: I believe that the mathematical theory of voting may be used to shed light on traditional rules of parliamentary procedure. For example, Black's [2] theory of voting on issues when the alternatives can be ordered so that each member's preferences are single-peaked highlights the importance of the chairman's casting vote in the case of an even number of voters. In this paper I study how another rule, division of the question on amendments, affects the creation of successful packages.
TL;DR: In this paper, a more complete justification of the side-jump model is given, which is used to derive the isothermal Nernst coefficient, where the side jump is assumed to have the same value for spin disorder as for impurity or phonon scattering.
Abstract: We recently showed that an electron wave packet undergoes an abrupt, sideways jump $\ensuremath{\Delta}y$ during scattering in the presence of spin-orbit interaction. This causes the Hall effect in ferromagnets around room temperature (${R}_{s}\ensuremath{\propto}{\ensuremath{\rho}}^{2}$). The value of the side jump per collision ($\ensuremath{\Delta}y\ensuremath{\approx}{10}^{\ensuremath{-}10}$ m) seems the same for impurity and phonon scattering. A more complete justification of the side-jump model is given here. This model is used to derive the isothermal Nernst coefficient ${Q}_{s}^{\mathrm{is}}$, giving ${Q}_{s}^{\mathrm{is}}\ensuremath{\propto}\ensuremath{\rho}T$, where $\ensuremath{\rho}$ is the resistivity. If spin-disorder scattering is also introduced, then the Hall conductivity ${\ensuremath{\gamma}}_{\mathrm{Hs}}$ is not affected, but the Nernst coefficient becomes ${Q}_{s}^{\mathrm{is}}=\ensuremath{-}T(\ensuremath{\alpha}+\ensuremath{\beta}\ensuremath{\rho})$. This formula agrees with the data of Kondorskii and Vasileva on Fe, Ni, Co, Gd, and Fe-Ni. The side jump is assumed to have the same value for spin disorder as for impurity or phonon scattering. The constant $\ensuremath{\alpha}$ is predicted to exist even in pure metals, in agreement with the above data but not with the Kondorskii theory.
TL;DR: Construction of a general model falsifying the Axiom of Extensionality shows that the general models of Henkin s article "Completeness in the Theory of Types" are not all sound interpretations of the system.
Abstract: Construction of a general model falsifying the Axiom of Extensionality shows that the general models of Henkin s article \"Completeness in the Theory of Types\" are not all sound interpretations of the system. A modification of the definition of general model remedies the situation. GENERAL MODELS AND EXTENSIONALITY by Peter B. Andrews §
TL;DR: In this article, a theoretical study of the spatial stability of Poiseuille flow in a rigid pipe to infinitesimal disturbances is presented, both axisymmetric and non-axisymetric disturbances are considered.
Abstract: A theoretical study of the spatial stability of Poiseuille flow in a rigid pipe to infinitesimal disturbances is presented. Both axisymmetric and non-axisymmetric disturbances are considered. The coupled, linear, ordinary differential equations governing the propagation of a disturbance that has a constant frequency and is imposed at a specified location in the fluid are solved numerically for the complex eigenvalues, or wavenumbers, each of which defines a mode of propagation. A series solution for small values of the pipe radius is derived and step-by-step integration to the pipe wall is then performed. In order to ascertain the number of eigenvalues within a closed region, an eigenvalue search technique is used. Results are obtained for Reynolds numbers up to 10000. For these Reynolds numbers it is found that the pipe Poiseuille flow is spatially stable to all infinitesimal disturbances.
TL;DR: The establishment of the shape of the low-response end of a dose-response curve by the use of large numbers of animals, and the statistical extrapolation of this information to predict a safe level for man, are deprecated.