The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Guy L Steele - One of the best experts on this subject based on the ideXlab platform.
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object oriented Units of Measurement
Conference on Object-Oriented Programming Systems Languages and Applications, 2004Co-Authors: Eric Allen, David Chase, Victor Luchangco, Janwillem Maessen, Guy L SteeleAbstract:Programs that manipulate physical quantities typically represent these quantities as raw numbers corresponding to the quantities' Measurements in particular Units (e.g., a length represented as a number of meters). This approach eliminates the possibility of catching errors resulting from adding or comparing quantities expressed in different Units (as in the Mars Climate Orbiter error [11]), and does not support the safe comparison and addition of quantities of the same dimension. We show how to formulate dimensions and Units as classes in a nominally typed object-oriented language through the use of statically typed metaclasses. Our formulation allows both parametric and inheritance poly-morphism with respect to both dimension and unit types. It also allows for integration of encapsulated Measurement systems, dynamic conversion factors, declarations of scales (including nonlinear scales) with defined zeros, and nonconstant exponents on dimension types. We also show how to encapsulate most of the "magic machinery" that handles the algebraic nature of dimensions and Units in a single meta-class that allows us to treat select static types as generators of a free abelian group.
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OOPSLA - Object-oriented Units of Measurement
Proceedings of the 19th annual ACM SIGPLAN Conference on Object-oriented programming systems languages and applications - OOPSLA '04, 2004Co-Authors: Eric Allen, David Chase, Victor Luchangco, Janwillem Maessen, Guy L SteeleAbstract:Programs that manipulate physical quantities typically represent these quantities as raw numbers corresponding to the quantities' Measurements in particular Units (e.g., a length represented as a number of meters). This approach eliminates the possibility of catching errors resulting from adding or comparing quantities expressed in different Units (as in the Mars Climate Orbiter error [11]), and does not support the safe comparison and addition of quantities of the same dimension. We show how to formulate dimensions and Units as classes in a nominally typed object-oriented language through the use of statically typed metaclasses. Our formulation allows both parametric and inheritance poly-morphism with respect to both dimension and unit types. It also allows for integration of encapsulated Measurement systems, dynamic conversion factors, declarations of scales (including nonlinear scales) with defined zeros, and nonconstant exponents on dimension types. We also show how to encapsulate most of the "magic machinery" that handles the algebraic nature of dimensions and Units in a single meta-class that allows us to treat select static types as generators of a free abelian group.
Eric J. Pauwels - One of the best experts on this subject based on the ideXlab platform.
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MKM/Calculemus/DML - Using MathML to represent Units of Measurement for improved ontology alignment
Lecture Notes in Computer Science, 2013Co-Authors: Eric J. PauwelsAbstract:Ontologies provide a formal description of concepts and their relationships in a knowledge domain. The goal of ontology alignment is to identify semantically matching concepts and relationships across independently developed ontologies that purport to describe the same knowledge. In order to handle the widest possible class of ontologies, many alignment algorithms rely on terminological and structural methods, but the often fuzzy nature of concepts complicates the matching process. However, one area that should provide clear matching solutions due to its mathematical nature, is Units of Measurement. Several ontologies for Units of Measurement are available, but there has been no attempt to align them, notwithstanding the obvious importance for technical interoperability. We propose a general strategy to map these (and similar) ontologies by introducing MathML to accurately capture the semantic description of concepts specified therein. We provide mapping results for three ontologies, and show that our approach improves on lexical comparisons.
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Using MathML to Represent Units of Measurement for Improved Ontology Alignment
arXiv: Artificial Intelligence, 2013Co-Authors: Eric J. PauwelsAbstract:Ontologies provide a formal description of concepts and their relationships in a knowledge domain. The goal of ontology alignment is to identify semantically matching concepts and relationships across independently developed ontologies that purport to describe the same knowledge. In order to handle the widest possible class of ontologies, many alignment algorithms rely on terminological and structural meth- ods, but the often fuzzy nature of concepts complicates the matching process. However, one area that should provide clear matching solutions due to its mathematical nature, is Units of Measurement. Several on- tologies for Units of Measurement are available, but there has been no attempt to align them, notwithstanding the obvious importance for tech- nical interoperability. We propose a general strategy to map these (and similar) ontologies by introducing MathML to accurately capture the semantic description of concepts specified therein. We provide mapping results for three ontologies, and show that our approach improves on lexical comparisons.
Eric Allen - One of the best experts on this subject based on the ideXlab platform.
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object oriented Units of Measurement
Conference on Object-Oriented Programming Systems Languages and Applications, 2004Co-Authors: Eric Allen, David Chase, Victor Luchangco, Janwillem Maessen, Guy L SteeleAbstract:Programs that manipulate physical quantities typically represent these quantities as raw numbers corresponding to the quantities' Measurements in particular Units (e.g., a length represented as a number of meters). This approach eliminates the possibility of catching errors resulting from adding or comparing quantities expressed in different Units (as in the Mars Climate Orbiter error [11]), and does not support the safe comparison and addition of quantities of the same dimension. We show how to formulate dimensions and Units as classes in a nominally typed object-oriented language through the use of statically typed metaclasses. Our formulation allows both parametric and inheritance poly-morphism with respect to both dimension and unit types. It also allows for integration of encapsulated Measurement systems, dynamic conversion factors, declarations of scales (including nonlinear scales) with defined zeros, and nonconstant exponents on dimension types. We also show how to encapsulate most of the "magic machinery" that handles the algebraic nature of dimensions and Units in a single meta-class that allows us to treat select static types as generators of a free abelian group.
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OOPSLA - Object-oriented Units of Measurement
Proceedings of the 19th annual ACM SIGPLAN Conference on Object-oriented programming systems languages and applications - OOPSLA '04, 2004Co-Authors: Eric Allen, David Chase, Victor Luchangco, Janwillem Maessen, Guy L SteeleAbstract:Programs that manipulate physical quantities typically represent these quantities as raw numbers corresponding to the quantities' Measurements in particular Units (e.g., a length represented as a number of meters). This approach eliminates the possibility of catching errors resulting from adding or comparing quantities expressed in different Units (as in the Mars Climate Orbiter error [11]), and does not support the safe comparison and addition of quantities of the same dimension. We show how to formulate dimensions and Units as classes in a nominally typed object-oriented language through the use of statically typed metaclasses. Our formulation allows both parametric and inheritance poly-morphism with respect to both dimension and unit types. It also allows for integration of encapsulated Measurement systems, dynamic conversion factors, declarations of scales (including nonlinear scales) with defined zeros, and nonconstant exponents on dimension types. We also show how to encapsulate most of the "magic machinery" that handles the algebraic nature of dimensions and Units in a single meta-class that allows us to treat select static types as generators of a free abelian group.
Zdravko Kravanja - One of the best experts on this subject based on the ideXlab platform.
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a review of footprint analysis tools for monitoring impacts on sustainability
Journal of Cleaner Production, 2012Co-Authors: Lidija Cucek, Jiři Jaromir Klemes, Zdravko KravanjaAbstract:Abstract This study presents an overview of footprints as defined indicators that can be used to measure sustainability. An overview of the definitions and Units of Measurement associated with environmental, social, and economic footprints is important because the definitions of footprints vary and are often expressed unclearly. Composite footprints combining two or more individual footprints are also assessed. These combinations produce multi-objective optimisation problems. Several tools for footprint(s)' evaluation are presented, including some of the numerous carbon footprint calculators, available calculators for other footprints, some ecological footprints-based, graph-based, and mathematical programming tools. A comprehensive overview is offered of footprint-based sustainability assessment.
Gianfranco Pacchioni - One of the best experts on this subject based on the ideXlab platform.
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Oxford Scholarship Online - Units of Measurement
Oxford Scholarship Online, 2018Co-Authors: Gianfranco PacchioniAbstract:This chapter discusses how performance is measured in science, such as through the role of citation metrics. Next, the chapter discusses the pros and cons of bibliometric indexes, and of ‘impact factor’, which was introduced by Eugene Garfield in 1955 but not widely used until twenty years later. The various ways that journals attempt to improve their impact factors, and how this will affect science, are also examined. Besides impact factor, the role played by indicators in evaluating scientists, such as the recently introduced h-index, is explored. Finally, fashions and trends in science are touched upon, illustrated with personal anecdotes from the author.
