Currently, physicists working in High Energy Physics experiments have to write their queries in general purpose programminglanguages using complex frameworks for accessing the data. This distracts them from their act...
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ISBN:
(纸本)0769524435
Currently, physicists working in High Energy Physics experiments have to write their queries in general purpose programminglanguages using complex frameworks for accessing the data. This distracts them from their actual work, namely data analysis, and reduces their productivity significantly. We have improved this situation by designing and implementing the first visual query language specific to this domain. Our goal was to provide a tool enabling physicists to formulate queries in their own terms and notation. In this paper we focus on the formal definition of our visual query language (including syntax and semantics). The meanings of our operators are well-defined by means of translational semantics;i.e., we map all elements of our language to a well-known NF2 algebra. We conclude with a discussion of the advantages of this formal design approach.
Constraint diagrams (Kent, 1997) are a complex diagrammatic notation designed to express logical statements especially for use in software specification and reasoning. Not surprisingly, since this is an expressive lan...
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ISBN:
(纸本)0769524435
Constraint diagrams (Kent, 1997) are a complex diagrammatic notation designed to express logical statements especially for use in software specification and reasoning. Not surprisingly, since this is an expressive language, there are some difficulties in reading the semantics of a diagram unambiguously. Some extra annotations (in the form of a reading tree) disambiguate the diagrams. However, this extra requirement (of drawing a reading tree) places a burden on the user. An attempt to remove the need for such a reading tree (or perhaps to automatically generate a reading tree, which could be altered by a user if they wished to) has been given via an algorithm to generate a default reading from the diagram. This algorithm is based on a number of principles - most of which are properties of the diagram. We wish to know whether these principles are intuitive and whether the default reading reflects a good proportion of users' intuitions, and we have performed a user-based study to test this.
Executable UML models (ire nowadays gaining interest in embedded systems design. This domain is strongly devoted to the modeling of reactive behavior using StateChart variants. In this context, the direct execution of...
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ISBN:
(纸本)0769524435
Executable UML models (ire nowadays gaining interest in embedded systems design. This domain is strongly devoted to the modeling of reactive behavior using StateChart variants. In this context, the direct execution of UML State Machines is an interesting alternative to native code generation approaches since it significantly increases portability. However, fully featured UML 2.0 State Machines may contain a broad set of features with complex execution semantics that differ significantly from other StateChart variants. This makes their direct execution complex and inefficient. In this paper, we demonstrate how such State Machines can be represented using a small subset of the UML State Machine features that enables efficient execution. We describe the necessary model transformations in terms of graph transformations and discuss the underlying semantics and implications for execution.
There are many common spreadsheet errors that traditional spreadsheet systems do not help users find. This paper presents a statically-typed spreadsheet language that adds additional information about the objects that...
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ISBN:
(纸本)0769524435
There are many common spreadsheet errors that traditional spreadsheet systems do not help users find. This paper presents a statically-typed spreadsheet language that adds additional information about the objects that the spreadsheet values represent. By annotating values with both units and labels, users denote both the system of measurement in which the values are expressed as well as the properties of the objects to which the values refer This information is used during computation to detect some invalid computations and allow users to identify properties of the resulting values.
Decentralized and complex systems can be powerful tools for modeling concepts in mathematics, science and engineering. StarLogo and NetLogo were the first systems to allow middle and high school children to build dyna...
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ISBN:
(纸本)0769524435
Decentralized and complex systems can be powerful tools for modeling concepts in mathematics, science and engineering. StarLogo and NetLogo were the first systems to allow middle and high school children to build dynamic models from many thousands of programmable particles. This has inspired Kedama: an authoring system that simplifies the scripting and construction of massively parallel models to allow more students to join in this new rich environment. This has given rise to new user interface and programminglanguage designs. Kedama has the following notable features: 1) Scripts in Kedama can be written in a graphical the scripting interface. & users are alleviated from syntax errors, and all program elements are visually presented to the user 2) Kedama is an extension of Squeak eToys: children who have learned to "script in the large" can use same techniques to "script in the small" with many thousands of objects. 3) The semantics and syntax are simplified but retain full power of expression. 4) The UI in Kedama is dynamic: scripts and other properties in Kedama can be dynamically modified while scripts are kept running. 5) Kedama is more pot-table, being able to run on more than two dozen types of platforms, including the most used around the world. 6) Kedama is fast. Various simulations typically run about 3 times faster than previous systems. This improvement made it possible to write different classes of examples.
During conceptual design of systems, the emphasis is on generating the system architecture: the configuration of sub-systems and the interactions between them. Ports, as locations of intended interaction, play an impo...
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During conceptual design of systems, the emphasis is on generating the system architecture: the configuration of sub-systems and the interactions between them. Ports, as locations of intended interaction, play an important role at this stage of design. They are convenient abstractions for representing the intended exchange of signals, energy or material;they can be applied at different levels of detail, across different energy domains, and to all aspects of design: form, function, and behavior. But to play this versatile role, ports need to be represented in an unambiguous yet flexible fashion, accommodating the differences in vocabulary and approach across different disciplines and perspectives. In this article, we introduce the semantic structure for such an unambiguous representation: a port ontology. The ontology formalizes the conceptualization of ports such that engineers and computer aided design applications can reason about component connections and interactions in system configuration. It defines ports in terms of form, function and behavior attributes and further includes axioms that can be used to support a variety of engineering design tasks, such as port refinement, port compatibility checking, and the instantiation of interaction models. A LEGO example is used to illustrate the ontology and its applications in conceptual design.
We specified a complete formal semantics for a generic continuous query language over streams and relations. Our semantics resolves any ambiguities present in informal language descriptions-it assigns an exact meaning...
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We specified a complete formal semantics for a generic continuous query language over streams and relations. Our semantics resolves any ambiguities present in informal language descriptions-it assigns an exact meaning to any query in the language, at any point in time, for any possible input streams and relations. Our generic language is built from a number of "black box" operators, whose semantics must be instantiated for a specific concrete language. As examples we instantiated a portion of CQL [ABW03], a language that includes SQL constructs, sliding windows over streams, and special-purpose relation-to-stream operators. In addition to clarifying the potentially subtle meaning of continuous queries, our formal semantics provides a tool for discovering and reasoning about equivalences within a given continuous query language, and for comparing expressiveness across different proposed languages.
Representing the sharing and exchanging data withmachine-readable format allows cooperative taskautomation. In this paper we propose an XML Schemaand semantic based relational data translation approach,which aims at p...
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ISBN:
(纸本)0780379411
Representing the sharing and exchanging data withmachine-readable format allows cooperative taskautomation. In this paper we propose an XML Schemaand semantic based relational data translation approach,which aims at providing a coherent and meaningful viewof the relational data and enabling distributed users tocooperate on large data volumes online. We define adirected-graph data model as the common data model,present a key-based relational schema reversereconstruction arithmetic to capture the full structuresand semantic constraints in relational schema, andpropose a constraints-preserving mapping algorithm totranslate relational data into the global XMLrepresentations.
This paper presents the reverse engineering tool JSPick, which recovers page signatures and form types from server pages based presentation layers. A formal semantics of the tool is given in pseudo-evaluation style.
ISBN:
(纸本)0769519024
This paper presents the reverse engineering tool JSPick, which recovers page signatures and form types from server pages based presentation layers. A formal semantics of the tool is given in pseudo-evaluation style.
Software reuse should be engineered as early as possible in the software development life cycle. The earlier reusability considerations are put into software development, the larger the payoff can be obtained from reu...
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ISBN:
(纸本)0780382420
Software reuse should be engineered as early as possible in the software development life cycle. The earlier reusability considerations are put into software development, the larger the payoff can be obtained from reuse. This paper briefly introduces the syntax and semantics of the TUG specification language. Some important but not comprehensive features of the language for reuse are presented with the aid of examples. Finally, specification reuse is illustrated with an analogy between a restaurant reservation system and a university registration system.
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