scholarly journals Demand analysis with partial predicates

2007 ◽  
Vol 7 (1-2) ◽  
pp. 153-182
Author(s):  
JULIO MARIÑO ◽  
ÁNGEL HERRANZ ◽  
JUAN JOSÉ MORENO-NAVARRO
Keyword(s):  
Program Transformation ◽  
Abstract Interpretation ◽  
The Other ◽  
Demand Analysis ◽  
Constraint Solving ◽  
Semantic Framework ◽  
Stepwise Manner ◽  
Strictness Analysis ◽  
Demand Equations ◽  
Partial Predicates

AbstractTo alleviate the inefficiencies caused by the interaction of the logic and functional sides, integrated languages may take advantage of demand information, i.e. knowing in advance which computations are needed and, to which extent, in a particular context. This work studies demand analysis – which is closely related to backwards strictness analysis – in a semantic framework of partial predicates, which in turn are constructive realizations of ideals in a domain. This will allow us to give a concise, unified presentation of demand analysis, to relate it to other analyses based on abstract interpretation or strictness logics, some hints for the implementation, and, more important, to prove the soundness of our analysis based on demand equations. There are also some innovative results. One of them is that a set constraint-based analysis has been derived in a stepwise manner using ideas taken from the area of program transformation. The other one is the possibility of using program transformation itself to perform the analysis, specially in those domains of properties where algorithms based on constraint solving are too weak.

scholarly journals Modular Constraint Solver Cooperation via Abstract Interpretation

2020 ◽  
Vol 20 (6) ◽  
pp. 848-863
Author(s):  
PIERRE TALBOT ◽  
ÉRIC MONFROY ◽  
CHARLOTTE TRUCHET
Keyword(s):  
Abstract Interpretation ◽  
Job Shop ◽  
Job Shop Scheduling ◽  
Constraint Solving ◽  
Bound Constraints ◽  
Ordered Structures ◽  
Constraint Solver ◽  
Abstract Domains ◽  
Theoretical Foundations ◽  
Modular Framework

AbstractCooperation among constraint solvers is difficult because different solving paradigms have different theoretical foundations. Recent works have shown that abstract interpretation can provide a unifying theory for various constraint solvers. In particular, it relies on abstract domains which capture constraint languages as ordered structures. The key insight of this paper is viewing cooperation schemes as abstract domains combinations. We propose a modular framework in which solvers and cooperation schemes can be seamlessly added and combined. This differs from existing approaches such as SMT where the cooperation scheme is usually fixed (e.g., Nelson-Oppen). We contribute to two new cooperation schemes: (i) interval propagators completion that allows abstract domains to exchange bound constraints, and (ii) delayed product which exchanges over-approximations of constraints between two abstract domains. Moreover, the delayed product is based on delayed goal of logic programming, and it shows that abstract domains can also capture control aspects of constraint solving. Finally, to achieve modularity, we propose the shared product to combine abstract domains and cooperation schemes. Our approach has been fully implemented, and we provide various examples on the flexible job shop scheduling problem.

scholarly journals Modeling U.S. Butter Consumption with Zero Observations

1995 ◽  
Vol 24 (1) ◽  
pp. 47-55 ◽  
Author(s):  
Steven T. Yen ◽  
Shew-Jiuan Su
Keyword(s):  
United States ◽  
Income Elasticity ◽  
The United States ◽  
The Other ◽  
Demand Analysis ◽  
Hurdle Model ◽  
Double Hurdle Model ◽  
Heteroscedastic Errors ◽  
Double Hurdle

A heteroscedastic double-hurdle model is used to investigate household butter consumption in the United States. Results suggest that failure to incorporate heteroscedastic errors may lead to unreliable elasticity estimates. Decomposition of the effects of variables leads to insightful information and makes the double-hurdle model a more useful tool in micro demand analysis. Larger and higher-income households are more likely to consume butter than others and also consume more, but income elasticity is very small. Age, region, and seasonality are among the other significant determinants of household butter consumption.

scholarly journals Static Mapping of Functional Programs: An Example in Signal Processing

1996 ◽  
Vol 5 (2) ◽  
pp. 121-135
Author(s):  
Jack B. Dennis
Keyword(s):  
Signal Processing ◽  
Program Transformation ◽  
The Other ◽  
Processing Element ◽  
Complex Signal ◽  
Massive Parallelism ◽  
Processing Elements ◽  
Program Description ◽  
The Given ◽  
Program Modules

Complex signal-processing problems are naturally described by compositions of program modules that process streams of data. In this article we discuss how such compositions may be analyzed and mapped onto multiprocessor computers to effectively exploit the massive parallelism of these applications. The methods are illustrated with an example of signal processing for an optical surveillance problem. Program transformation and analysis are used to construct a program description tree that represents the given computation as an acyclic interconnection of stream-processing modules. Each module may be mapped to a set of threads run on a group of processing elements of a target multiprocessor. Performance is considered for two forms of multiprocessor architecture, one based on conventional DSP technology and the other on a multithreaded-processing element design.

Identifying logical dummy activities in an activity-on-arrow network

2008 ◽  
Vol 35 (7) ◽  
pp. 739-743
Author(s):  
Kyunghwan Kim
Keyword(s):  
Construction Projects ◽  
Heuristic Method ◽  
The Other ◽  
Multiple Relationships ◽  
Critical Problem ◽  
Stepwise Manner ◽  
The Creation ◽  
One To One

The activity-on-arrow (AOA) method can be used in construction projects depending on the project condition, although it is relatively inefficient as compared to the activity-on-node (AON) method. The most critical problem of the AOA method that is yet to be resolved is the application of a logical dummy activity (dummy). This paper presents a heuristic method that can be used for systematically identifying and applying logical dummies during the creation of an AOA network based on predefined activity dependencies. The heuristic method first identifies logical dummies of one-to-one relationships, and then detects the other multiple relationships in a stepwise manner to remove the redundancies therein.

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).

scholarly journals Light-Dependent Eye Coupling during the Optokinetic Response of the Crab Carcinus Maenas (L.)

1985 ◽  
Vol 119 (1) ◽  
pp. 103-114
Author(s):  
H.-O. NALBACH ◽  
P. THIER ◽  
D. VARJÚ
Keyword(s):  
Horizontal Plane ◽  
Relative Phase ◽  
Carcinus Maenas ◽  
Biological Significance ◽  
The Other ◽  
Low Light ◽  
Optokinetic Response ◽  
Variable Strength ◽  
Stepwise Manner ◽  
Logarithmic Relationship

1. The movements of both distal eye stalks in the horizontal plane, elicited by optokinetic stimuli, have been recorded simultaneously. 2. A panorama was split into two separate halves and was either oscillated around the animal in a sinusoidal fashion or displaced in a stepwise manner. Both eyes could be stimulated independently. 3. The stimuli on both sides differed either (a) in the illumination, or (b) in the total amount of light impinging upon the eyes or (c) in the relative phase of the sinusoidal stimuli to either eye. 4. As the illumination decreases the optokinetic response weakens. 5. If one eye has no or only weak optokinetic input, it will be driven by the other eye. The response mediated by the contralateral optokinetic stimulus diminishes if the amount of light impinging upon the driven eye is increased. 6. There is a logarithmic relationship between the response of the driving eye and that of the driven eye. 7. The possible biological significance of these relationships is seen in the enhanced coupling at low light intensities. 8. The variable strength of coupling and possible roles of movable eyes are discussed.

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