A relational approach to strictness analysis for higher-order polymorphic functions

1991 ◽  
Author(s):  
Samson Abramsky ◽  
Thomas P. Jensen
Keyword(s):  
Higher Order ◽  
Relational Approach ◽  
Strictness Analysis

scholarly journals Bounded Fixed Point Iteration

1991 ◽  
Vol 20 (359) ◽  
Author(s):  
Hanne Riis Nielson ◽  
Flemming Nielson
Keyword(s):  
Fixed Point ◽  
Abstract Interpretation ◽  
Higher Order ◽  
Monotone Functions ◽  
Additive Functions ◽  
Fixed Point Iteration ◽  
Exponential Bound ◽  
Strictness Analysis ◽  
Long Chains

In the context of abstract interpretation for languages without higher-order features we study the number of times a functional need to be unfolded in order to give the least fixed point. For the cases of total or monotone functions we obtain an exponential bound and in the case of strict and additive (or distributive) functions we obtain a quadratic bound. These bounds are shown to be tight in that sufficiently long chains of functions can be shown to exist. Specializing the case of strict and additive functions to functionals of a form that would correspond to iterative programs we show that a linear bound is tight. This is related to several analyses studied in the literature (including strictness analysis).

The making of mind

2017 ◽  
Vol 26 (1) ◽  
pp. 79-81
Author(s):  
Russell Meares
Keyword(s):  
Higher Order ◽  
Relational Approach ◽  
Immediate Experience

Objectives The ordinary, ongoing sense of personal existing, variously called higher order consciousness, mind, or self, is disintegrated, constricted and distorted in those who have suffered repetitive psychological traumata. Their speech has the form of a ‘chronicle’, literal and asymbolic. This paper offers a condensed rationale for a relational approach to this, so far, neglected problem. Conclusions: A restorative and generative kind of relatedness is ‘natural’, the propensity for it being given to us by our biological heritage. Its first form is a game between babies and caregivers, a ‘proto-conversation’. Principles derived from this, and related developmental behaviours, guide a form of therapeutic relatedness consisting of an interactive, to-and-fro ‘patterning’ of verbal ‘pictures’, or analogues, of the subject’s immediate experience. The analogue is the first form of symbol, the use of which is the hallmark of the human.

A syntactic method for finding least fixed points of higher-order functions over finite domains

1997 ◽  
Vol 7 (4) ◽  
pp. 357-394
Author(s):  
TYNG-RUEY CHUANG ◽  
BENJAMIN GOLDBERG
Keyword(s):  
Fixed Point ◽  
Fixed Points ◽  
Normal Forms ◽  
Abstract Interpretation ◽  
Higher Order ◽  
Semantic Domain ◽  
Recent Developments ◽  
Strictness Analysis ◽  
Finite Domains ◽  
Higher Order Functions

This paper describes a method for finding the least fixed points of higher-order functions over finite domains using symbolic manipulation. Fixed point finding is an essential component in the calculation of abstract semantics of functional programs, providing the foundation for program analyses based on abstract interpretation. Previous methods for fixed point finding have primarily used semantic approaches, which often must traverse large portions of the semantic domain even for simple programs. This paper provides the theoretical framework for a syntax-based analysis that is potentially very fast. The proposed syntactic method is based on an augmented simply typed lambda calculus where the symbolic representation of each function produced in the fixed point iteration is transformed to a syntactic normal form. Normal forms resulting from successive iterations are then compared syntactically to determine their ordering in the semantic domain, and to decide whether a fixed point has been reached. We show the method to be sound, complete and compositional. Examples are presented to show how this method can be used to perform strictness analysis for higher-order functions over non-flat domains. Our method is compositional in the sense that the strictness property of an expression can be easily calculated from those of its sub-expressions. This is contrary to most strictness analysers, where the strictness property of an expression has to be computed anew whenever one of its subexpressions changes. We also compare our approach with recent developments in strictness analysis.

scholarly journals Strictness analysis for higher-order functions

1986 ◽  
Vol 7 ◽  
pp. 249-278 ◽  
Author(s):  
Geoffrey L. Burn ◽  
Chris Hankin ◽  
Samson Abramsky
Keyword(s):  
Higher Order ◽  
Strictness Analysis ◽  
Higher Order Functions

Untyped strictness analysis

1995 ◽  
Vol 5 (1) ◽  
pp. 37-49 ◽  
Author(s):  
Christine Ernoult ◽  
Alan Mycroft
Keyword(s):  
Higher Order ◽  
Strictness Analysis

AbstractWe re-express Hudak and Young's higher-order strictness analysis for the untyped λ-calculus in a conceptually simpler and more semantically-based manner. We show our analysis to be a sound abstraction of Hudak and Young's which is also complete in a sense we make precise.

Dual systems for all: Higher-order, role-based relational reasoning as a uniquely derived feature of human cognition

2019 ◽  
Vol 42 ◽  
Author(s):  
Daniel J. Povinelli ◽  
Gabrielle C. Glorioso ◽  
Shannon L. Kuznar ◽  
Mateja Pavlic
Keyword(s):  
Temporal Reasoning ◽  
Higher Order ◽  
Important Case ◽  
Human Cognition ◽  
Relational Reasoning ◽  
Dual Systems ◽  
First Order ◽  
Reasoning System ◽  
Role Based

Abstract Hoerl and McCormack demonstrate that although animals possess a sophisticated temporal updating system, there is no evidence that they also possess a temporal reasoning system. This important case study is directly related to the broader claim that although animals are manifestly capable of first-order (perceptually-based) relational reasoning, they lack the capacity for higher-order, role-based relational reasoning. We argue this distinction applies to all domains of cognition.

Quantitative EPMA of nitrogen : A tricky element in the electron-probe microanalyzer

1992 ◽  
Vol 50 (2) ◽  
pp. 1622-1623
Author(s):  
G.F. Bastin ◽  
H.J.M. Heijligers
Keyword(s):  
Background Subtraction ◽  
Electron Probe ◽  
Detection System ◽  
Higher Order ◽  
Light Elements ◽  
Strong Suppression ◽  
Electron Probe Microanalyzer ◽  
Quantitative Epma ◽  
Peak Count ◽  
Lead Stearate

Among the ultra-light elements B, C, N, and O nitrogen is the most difficult element to deal with in the electron probe microanalyzer. This is mainly caused by the severe absorption that N-Kα radiation suffers in carbon which is abundantly present in the detection system (lead-stearate crystal, carbonaceous counter window). As a result the peak-to-background ratios for N-Kα measured with a conventional lead-stearate crystal can attain values well below unity in many binary nitrides . An additional complication can be caused by the presence of interfering higher-order reflections from the metal partner in the nitride specimen; notorious examples are elements such as Zr and Nb. In nitrides containing these elements is is virtually impossible to carry out an accurate background subtraction which becomes increasingly important with lower and lower peak-to-background ratios. The use of a synthetic multilayer crystal such as W/Si (2d-spacing 59.8 Å) can bring significant improvements in terms of both higher peak count rates as well as a strong suppression of higher-order reflections.

Effects of Higher-Order Laue Zone reflections on structure images

1993 ◽  
Vol 51 ◽  
pp. 450-451
Author(s):  
H. S. Kim ◽  
S. S. Sheinin
Keyword(s):  
Wave Vector ◽  
Theoretical Calculations ◽  
Reciprocal Lattice ◽  
Image Plane ◽  
Bloch Wave ◽  
Dynamical Theory ◽  
Higher Order ◽  
Lattice Image ◽  
Lattice Vector ◽  
Image Position

The importance of image simulation in interpreting experimental lattice images is well established. Normally, in carrying out the required theoretical calculations, only zero order Laue zone reflections are taken into account. In this paper we assess the conditions for which this procedure is valid and indicate circumstances in which higher order Laue zone reflections may be important. Our work is based on an analysis of the requirements for obtaining structure images i.e. images directly related to the projected potential. In the considerations to follow, the Bloch wave formulation of the dynamical theory has been used.The intensity in a lattice image can be obtained from the total wave function at the image plane is given by: where ϕg(z) is the diffracted beam amplitide given by In these equations,the z direction is perpendicular to the entrance surface, g is a reciprocal lattice vector, the Cg(i) are Fourier coefficients in the expression for a Bloch wave, b(i), X(i) is the Bloch wave excitation coefficient, ϒ(i)=k(i)-K, k(i) is a Bloch wave vector, K is the electron wave vector after correction for the mean inner potential of the crystal, T(q) and D(q) are the transfer function and damping function respectively, q is a scattering vector and the summation is over i=l,N where N is the number of beams taken into account.

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