Stochastic Growth: Asymptotic Distributions.

This note studies conditions under which sequences of capital per head generated by stochastic optimal accumulation models have law of large numbers and central limit properties. The regularity condition used on the productivity shock is somewhat different to that of previous studies. In particular, no restrictions are placed on its support. Instead, an "average contraction" property is required on the law of motion.CAPITAL ; PRODUCTIVITY ; ECONOMIC MODELS

Microstructure of horseshoe nails using neutron diffraction

Neutron diffraction allows non-destructive testing of the bulk microstructure of mechanical components. The microstructures of horseshoe nails made through three different processes have been explored as a function of position along the nail. Despite all nails being made of similar plain low carbon steel and being process annealed after manufacture, the microstructures are far from the same. Nails made from strip, using a cold forging stamping process, show narrower diffraction peaks indicating a narrower distribution of lattice parameters and also show diffraction peak intensity ratios closer to those expected for unstrained steel. Thus the distribution of the orientation of grains in these nails is closer to that of undistorted steel compared to nails made through the other two processes considered – one a drawing from wire, the other a combination of rolling and cold forging. The blades of the drawn nails showed little preferred orientation but the converse was true in the heads. Differing patterns of preferred orientation suggest that the various manufacturing approaches result in substantially different mechanical advantages for the three types of nails, a result in accord with mechanical testing

Log-Linearization of Perturbed Dynamical Systems, With Applications to Optimal Growth.

It is common to study the asymptotic properties of log-linear stochastic systems by analyzing the behaviour of their linear counterparts. In this paper a formal justification for analysis by log-linearization is given. As an application, a new existence, uniqueness and stability condition is derived for equilibria in a standard class of multisector growth models with stochastic production. The condition can be seen as a generalization of existing equilibrium conditions for this class of models.BEHAVIOUR ; GROWTH MODELS ; PRODUCTION

Investigation and improvement of zinc electrodes for electrochemical cells quarterly report no. 2, oct. - dec. 1964

Influence of separator and surfactant on growth rate of zinc deposits in electrochemical cell

Some Stability Results for Markovian Economic Semigroups

The paper studies existence, uniqueness and stability of stationary equilibrium distributions in a class of stochastic dynamic models common to economic analysis. The stability conditions provided are suitable for treating multi-sector models and nonlinear time series models with unbounded state.Markov processes, asymptotic stability, semigroups

Study to investigate and improve the zinc electrode for spacecraft electrochemical cells Quarterly report

Zinc electrode improvement work for use in spacecraft electrochemical cell

Economic Networks: Theory and Computation

This textbook is an introduction to economic networks, intended for students and researchers in the fields of economics and applied mathematics. The textbook emphasizes quantitative modeling, with the main underlying tools being graph theory, linear algebra, fixed point theory and programming. The text is suitable for a one-semester course, taught either to advanced undergraduate students who are comfortable with linear algebra or to beginning graduate students.Comment: Textbook homepage is https://quantecon.github.io/book-networks/intro.htm

Computing expected moments of the R\'enyi parking problem on the circle

A highly accurate and efficient method to compute the expected values of the count, sum, and squared norm of the sum of the centre vectors of a random maximal sized collection of non-overlapping unit diameter disks touching a fixed unit-diameter disk is presented. This extends earlier work on R\'enyi's parking problem [Magyar Tud. Akad. Mat. Kutat\'{o} Int. K\"{o}zl. 3 (1-2), 1958, pp. 109-127]. Underlying the method is a splitting of the the problem conditional on the value of the first disk. This splitting is proven and then used to derive integral equations for the expectations. These equations take a lower block triangular form. They are solved using substitution and approximation of the integrals to very high accuracy using a polynomial approximation within the blocks

The verbal transformation effect and the perceptual organization of speech:influence of formant transitions and F0-contour continuity

This study explored the role of formant transitions and F0-contour continuity in binding together speech sounds into a coherent stream. Listening to a repeating recorded word produces verbal transformations to different forms; stream segregation contributes to this effect and so it can be used to measure changes in perceptual coherence. In experiment 1, monosyllables with strong formant transitions between the initial consonant and following vowel were monotonized; each monosyllable was paired with a weak-transitions counterpart. Further stimuli were derived by replacing the consonant-vowel transitions with samples from adjacent steady portions. Each stimulus was concatenated into a 3-min-long sequence. Listeners only reported more forms in the transitions-removed condition for strong-transitions words, for which formant-frequency discontinuities were substantial. In experiment 2, the F0 contour of all-voiced monosyllables was shaped to follow a rising or falling pattern, spanning one octave. Consecutive tokens either had the same contour, giving an abrupt F0 change between each token, or alternated, giving a continuous contour. Discontinuous sequences caused more transformations and forms, and shorter times to the first transformation. Overall, these findings support the notion that continuity cues provided by formant transitions and the F0 contour play an important role in maintaining the perceptual coherence of speech

Stochastic Optimal Growth with Unbounded Shock.

This paper considers a neoclassical optimal growth problem where the shock that perturbs the economy in each time period is potentially unbounded on the state space. Sufficient conditions for existence, uniqueness and stability of equilibria are derived in terms of the primitives of the model using new techniques from the field of perturbed dynamical systems.ECONOMIC GROWTH ; ECONOMIC MODELS