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Unifying Framework for Optimizations in non-boolean Formalisms

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arXiv 2022年

作者： Lierler, Yuliya University of Nebraska Omaha United States

Search-optimization problems are plentiful in scientific and engineering domains. Artificial intelligence has long contributed to the development of search algorithms and declarative programming languages geared towards solving and modeling search-optimization problems. Automated reasoning and knowledge representation are the subfields of AI that are particularly vested in these developments. Many popular automated reasoning paradigms provide users with languages supporting optimization statements. Recall integer linear programming, MaxSAT, optimization satisfiability modulo theory, (constraint) answer set programming. These paradigms vary significantly in their languages in ways they express quality conditions on computed solutions. Here we propose a unifying framework of so called extended weight systems that eliminates syntactic distinctions between paradigms. They allow us to see essential similarities and differences between optimization statements provided by distinct automated reasoning languages. We also study formal properties of the proposed systems that immediately translate into formal properties of paradigms that can be captured within our framework. Under consideration in theory and practice of logic programming (TPLP). © 2022, CC BY.

关键词： Integer programming

Symbolic Parameter Learning in Probabilistic Answer Set programming

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arXiv 2024年

作者： Azzolini, Damiano Gentili, Elisabetta Riguzzi, Fabrizio Department of Environmental and Prevention Sciences University of Ferrara Ferrara Italy Department of Engineering University of Ferrara Ferrara Italy Department of Mathematics and Computer Science University of Ferrara Ferrara Italy

Parameter learning is a crucial task in the field of Statistical Relational Artificial Intelligence: given a probabilistic logic program and a set of observations in the form of interpretations, the goal is to learn the probabilities of the facts in the program such that the probabilities of the interpretations are maximized. In this paper, we propose two algorithms to solve such a task within the formalism of Probabilistic Answer Set programming, both based on the extraction of symbolic equations representing the probabilities of the interpretations. The first solves the task using an off-the-shelf constrained optimization solver while the second is based on an implementation of the Expectation Maximization algorithm. Empirical results show that our proposals often outperform existing approaches based on projected answer set enumeration in terms of quality of the solution and in terms of execution time. The paper has been accepted at the ICLP2024 conference and is under consideration in theory and practice of logic programming (TPLP). © 2024, CC BY.

关键词： Expectation maximization algorithm

Using SWISH to realise interactive web based tutorials for logic based languages

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arXiv 2018年

作者： Wielemaker, Jan Riguzzi, Fabrizio Kowalski, Bob Lager, Torbjörn Sadri, Fariba Calejo, Miguel Centrum Wiskunde & Informatica Amsterdam Netherlands Imperial College London United Kingdom University of Gothenburg Logical Contracts

programming environments have evolved from purely text based to using graphical user interfaces, and now we see a move towards web based interfaces, such as Jupyter. Web based interfaces allow for the creation of interactive documents that consist of text and programs, as well as their output. The output can be rendered using web technology as, e.g., text, tables, charts or graphs. This approach is particularly suitable for capturing data analysis workflows and creating interactive educational material. This article describes SWISH, a web front-end for Prolog that consists of a web server implemented in SWI-Prolog and a client web application written in JavaScript. SWISH provides a web server where multiple users can manipulate and run the same material, and it can be adapted to support Prolog extensions. In this paper we describe the architecture of SWISH, and describe two case studies of extensions of Prolog, namely Probabilistic logic programming (PLP) and logic Production System (LPS), which have used SWISH to provide tutorial sites. Under consideration in theory and practice of logic programming (TPLP) Copyright © 2018, The Authors. All rights reserved.

关键词： Web services

Top-down and bottom-up evaluation procedurally integrated

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arXiv 2018年

作者： Warren, David S. Stony Brook University Stony BrookNY11794-4400 United States XSB Inc. SetauketNY11733 United States

This paper describes how XSB combines top-down and bottom-up computation through the mechanisms of variant tabling and subsumptive tabling with abstraction, respectively. It is well known that top-down evaluation of logical rules in Prolog has a procedural interpretation as recursive procedure invocation (Kowalski 1986). Tabling adds the intuition of short-circuiting redundant computations (Warren 1992). This paper shows how to introduce into tabled logic program evaluation a bottom-up component, whose procedural intuition is the initialization of a data structure, in which a relation is initially computed and filled, on first demand, and then used throughout the remainder of a larger computation for efficient lookup. This allows many Prolog programs to be expressed fully declaratively, programs which formerly required procedural features, such as assert, to be made efficient. This paper is under consideration for acceptance in theory and practice of logic programming (TPLP). Copyright © 2018, The Authors. All rights reserved.

关键词： logic programming

Incremental maintenance of overgrounded logic programs with tailored simplifications

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arXiv 2020年

作者： Ianni, Giovambattista Pacenza, Francesco Zangari, Jessica Department of Mathematics and Computer Science University of Calabria Rende Italy

The repeated execution of reasoning tasks is desirable in many applicative scenarios, such as stream reasoning and event processing. When using answer set programming in such contexts, one can avoid the iterative generation of ground programs thus achieving a significant payoff in terms of computing time. However, this may require some additional amount of memory and/or the manual addition of operational directives in the declarative knowledge base at hand. We introduce a new strategy for generating series of monotonically growing propositional programs. The proposed overgrounded programs with tailoring (OPTs) can be updated and reused in combination with consecutive inputs. With respect to earlier approaches, our tailored simplification technique reduces the size of instantiated programs. A maintained OPT slowly grows in size from an iteration to another while the update cost decreases, especially in later iterations. In this paper we formally introduce tailored embeddings, a family of equivalence-preserving ground programs which are at the theoretical basis of OPTs and we describe their properties. We then illustrate an OPT update algorithm and report about our implementation and its performance. This paper is under consideration in theory and practice of logic programming (TPLP). Copyright © 2020, The Authors. All rights reserved.

关键词： logic programming

Field data analysis of multi spindle lathes for a proven-in-use assessment 27th

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Field data analysis of multi spindle lathes for a proven-in-...

27th European Safety and Reliability Conference, ESREL 2017

作者： Nowizki, N. Zeiler, P. Bertsche, B. Mödden, H. Institute of Machine Components University of Stuttgart Germany VDW—German Machine Tool Builders Association Frankfurt Germany

ISBN: (纸本)9781138629370

In this paper, operating data of lathes is analyzed with regard to the specifications of the ISO 13849-1. The Weibull analysis is based on machine running times of 1519 multi spindle automatic lathes. The analyzed safety function, "workpiece clamping" is achieving a maximum performance level b (PL b) for lathes with a standard PLC (programmable logic controller) according to the approach of ISO 13849–1, whereas at least PL c is required. However, in reality, the considered machines are operating for up to thirteen years without any loss of the safety function due to technical failure. The quantitative measure of the performance level is the "average probability of a dangerous failure per hour". Since there is uncertainty regarding the interpretation of this measure, the main possibilities are discussed and a cor-responding parameter is chosen as reference. Since there is no known shape parameter b for the failure of the considered safety function, a parameter study with different shape parameters is carried out. © 2017 Taylor & Francis Group, London.

关键词： C (programming language)

Constraint propagation for soft constraints: Generalization and termination conditions 6th

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6th International Conference on Principles and practice of Constraint programming, CP2000

作者： Bistarelli, S. Gennari, R. Rossi, F. Università di Pisa Dipartimento di Informatica Corso Italia 40 Pisa56125 Italy ILLC Institute of Logic Language and Computation University of Amsterdam N. Doelenstraat 15 Amsterdam1012 CP Netherlands Università di Padova Dipartimento di Matematica Pura ed Applicata Via Belzoni 7 Padova35131 Italy

ISBN: (纸本)3540410538

Soft constraints based on semirings are a generalization of classical constraints, where tuples of variables’ values in each soft constraint are uniquely associated to elements from an algebraic structure called semiring. This framework is able to express, for example, fuzzy, classical, weighted, valued and over-constrained constraint problems. Classical constraint propagation has been extended and adapted to soft constraints by defining a schema for soft local consistency [BMR97]. On the other hand, in [Apt99a,Apt99b] it has been proved that most of the well known constraint propagation algorithms for classical constraints can be cast within a single schema. In this paper we combine these two schema and we show how the framework of [Apt99a,Apt99b] can be used for soft constraints. In doing so, we generalize the concept of soft local consistency, and we prove some convenient properties about its termination. © Springer-Verlag Berlin Heidelberg 2000.

关键词： Constraint theory

THE ROLE OF CREW ROSTERING IN SUSTAINABLE OPERATIONS: A CASE STUDY IN AIRLINES

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INTERNATIONAL JOURNAL OF INDUSTRIAL ENGINEERING-theory APPLICATIONS AND practice 2022年第3期29卷 389-412页

作者： Sarigol, Ilkan Ozdemir, Rifat AlAjmia, Amal AlShammaria, Anwar AlKafeefa, Mariam Bukhsha, Mona Al Ajmia, Reem Kranz Wolfe Associates Herent Belgium Amer Univ Middle East Coll Engn & Technol Kuwait Kuwait

The airline industry has evolved significantly in recent years, and the emphasis on minimizing the cost and risk of operational disruptions has been shifted, in part, to satisfaction and fairness in the assignment of crew members. The crew rostering is the phase of flight schedules in which crew members are assigned to rosters based on their preferences and fairness in terms of balanced flight times between crew members. The satisfaction of the crew members depends on how much their preferences are met in the rosters. In this study, the crew rostering problem with cabin members' preferences is formulated as a mixed-integer goal programming model with three objective functions: total satisfaction score, deviation from average satisfaction score, and deviation from average flight hours. The importance of these objectives is imprecise from the flight management system perspective, so this study proposes a fuzzy goal programming model to solve the crew rostering problem with the preferences. The paper is organized based on a case study gathered from an airline in Kuwait. The results showed that incorporating pilot preferences leads to better rosters in terms of pilot satisfaction. However, increasing the number of pilots in consideration or the flight evaluation percentage does not lead to better rosters. The case study also sheds light on the links between the crew roster and sustainable operations.

关键词： Crew Rostering Sustainable Operations Humanitarian Operations Employee Preference Fuzzy logic

Model checking for probability and time: from theory to practice

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Model checking for probability and time: from theory to prac...

Annual Symposium on logic in Computer Science

作者： M. Kwiatkowska School of Computer Science University of Binningham Birmingham UK

Probability features increasingly often in software and hardware systems: it is used in distributed coordination and routing problems, to model fault-tolerances and performance, and to provide adaptive resource management strategies. Probabilistic model checking is an automatic procedure for establishing if a desired property holds in a probabilistic specifications such as "leader election is eventually resolved with probability 1", "the chance of shutdown occurring is at most 0.01%", and "the probability that a message will be delivered within 30ms is at least 0.75". A probabilistic model checker calculates the probability of a given temporal logic property being satisfied, as opposed to validity. In contrast to conventional model checkers, which rely on reachability analysis of the underlying transition system graph, probabilistic model checking additionally involves numerical solutions of linear equations and linear programming problems. This paper reports our experience with implementing PRISM (***//spl sim/dxp/prism), a probabilistic symbolic model checker, demonstrates its usefulness in analyzing real-world probabilistic protocols, and outlines future challenges for this research direction.

关键词： Software performance Software systems Hardware Routing Fault tolerant systems Resource management Nominations and elections Probability Probabilistic logic logic programming