The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform

Alfred Strohmeier - One of the best experts on this subject based on the ideXlab platform.

  • UML - From use cases to system Operation Specifications
    Lecture Notes in Computer Science, 2000
    Co-Authors: Shane Sendall, Alfred Strohmeier
    Abstract:

    The purpose of this paper is to first showcase the concept of an Operation schema a precise form of system-level Operation Specification and secondly show how Operation schemas enhance development when they are used as a supplement to use case descriptions. An Operation schema declaratively describes the effects of a system Operation by pre- and postconditions using the Object Constraint Language (OCL), as defined by the Unified Modeling Language (UML). In particular, the paper highlights techniques to map use cases to Operation schemas and discusses the advantages of doing so in terms of clarifying the granularity and purpose of use cases and providing a precise Specification of system behavior.

  • Descriptive Object-Oriented Operation Specification for UML
    2000
    Co-Authors: Alfred Strohmeier, Shane Sendall
    Abstract:

    The purpose of this paper is to show how system Operations can be specified by pre- and postconditions using the Object Constraint Language (OCL), as defined by the Unified Modeling Language (UML) Specification, and how these system Operation Specifications relate to the analysis class model and other models of the analysis phasis. It is also shown how the communication between the system and actors by event sending can be modeled. The result is a system behavior model at a higher-level of abstraction than the one provided by collaboration diagrams, which concentrate on method invocations between objects.

Shane Sendall - One of the best experts on this subject based on the ideXlab platform.

  • UML - From use cases to system Operation Specifications
    Lecture Notes in Computer Science, 2000
    Co-Authors: Shane Sendall, Alfred Strohmeier
    Abstract:

    The purpose of this paper is to first showcase the concept of an Operation schema a precise form of system-level Operation Specification and secondly show how Operation schemas enhance development when they are used as a supplement to use case descriptions. An Operation schema declaratively describes the effects of a system Operation by pre- and postconditions using the Object Constraint Language (OCL), as defined by the Unified Modeling Language (UML). In particular, the paper highlights techniques to map use cases to Operation schemas and discusses the advantages of doing so in terms of clarifying the granularity and purpose of use cases and providing a precise Specification of system behavior.

  • Descriptive Object-Oriented Operation Specification for UML
    2000
    Co-Authors: Alfred Strohmeier, Shane Sendall
    Abstract:

    The purpose of this paper is to show how system Operations can be specified by pre- and postconditions using the Object Constraint Language (OCL), as defined by the Unified Modeling Language (UML) Specification, and how these system Operation Specifications relate to the analysis class model and other models of the analysis phasis. It is also shown how the communication between the system and actors by event sending can be modeled. The result is a system behavior model at a higher-level of abstraction than the one provided by collaboration diagrams, which concentrate on method invocations between objects.

M. Ancona - One of the best experts on this subject based on the ideXlab platform.

  • Inheritance and Subtyping
    1991
    Co-Authors: M. Ancona
    Abstract:

    A method for implementing subtyping and inheritance, as independent features of object-oriented languages, is presented. There are at least two reasons for decoupling subtyping from inheritance: the negative influence on encapsulation and the different perspective of Specification inheritance (subtyping) and implementation inheritance (code sharing). In our approach, subtyping and inheritance are defined in two independent constructs: the class module and the implementation module which are separately compiled. Subtyping is declared in the class module which contains all the public definitions of the class (e.g., types and Operation signatures), while inheritance is defined in the implementation module, which contains the implementations of all the Operations of the class. The class module includes assertions which are an algorithmic form of Operation Specification.

  • Inheritance and subtyping (object-oriented databases)
    [Proceedings] 1991 Symposium on Applied Computing, 1
    Co-Authors: M. Ancona
    Abstract:

    A method for implementing subtyping and inheritance, as independent features of object-oriented languages, is presented. There are at least two reasons for decoupling subtyping from inheritance: the negative influence on encapsulation and the different perspective of Specification inheritance (subtyping) and implementation inheritance (code sharing). Subtyping and inheritance are defined in two independent constructs: the class module and the implementation module which are separately compiled. Subtyping is declared in the class module which contains all the public definitions of the class (e.g., types ad Operation signatures), while inheritance is defined in the implementation module, which contains the implementations of all the Operations of the class. The class module includes assertions which are an algorithmic form of Operation Specification. >

Chen Ji-bin - One of the best experts on this subject based on the ideXlab platform.

Kristofer Bengtsson - One of the best experts on this subject based on the ideXlab platform.

  • flexible Specification of Operation behavior using multiple projections
    IEEE Transactions on Automation Science and Engineering, 2014
    Co-Authors: Kristofer Bengtsson, Bengt Lennartson
    Abstract:

    The execution behavior of a system or a product can often be specified by a set of Operations (sometimes called tasks, actions or activities). The process to specify these Operations seems to be a real challenge in various situations, for example when designing automation systems or keeping track of the work at an emergency department. To be flexible during design and development, is about coping with uncertainty. However, in practice, specifying Operation behavior is often quite inflexible because every possible execution route is explicitly defined. This approach is sometimes refereed to as point-based engineering, which is characterized by the early selection and approval of a single “best” specific solution. This approach can result in neither a robust nor a flexible design process with many rework iterations. This paper instead suggests a set-based Operation Specification approach that does not explicitly defines Operation routes, where instead the Operation behavior is specified using the execution restrictions in transition conditions for each Operation. This enables the possibility to create multiple projections of the Operation relations to enable better understanding. This is accomplished by creating various Sequences of Operations, sequences of Operations (SOP), including a multiplicity of sequences and Operation relations. Two example case studies are presented, where the first show the development of an automation system and the second study uses sequence projections in an emergency department at a hospital to handle the complex and flexible Operation (task) behavior.

  • Operation Specification for Sequence Planning and Automation Design
    2010
    Co-Authors: Kristofer Bengtsson
    Abstract:

    When designing an automation system, an important challenge is to specify the different tasks, or Operations, of the system. This has become a problematic bottle-neck in industry, since the rising needs on manufacturing flexibility increases the complexity of the entire manufacturing system, as well as its control function. This thesis studies how to specify the manufacturing Operations when developing an automation system, especially how to plan the Operations and the relations among them, called sequence planning, and how to implement them in a programmable logic controller (PLC). To manage the complete automation development process, a formal language called sequences of Operations, SOP, is introduced. This language, together with a set of methods, are used to represent, identify and visualize complex Operation relations, so that the behavior of the system can be understood. By the use of different views or perspectives, the sequence of Operations related to e.g the part flow, robot Operations or operator tasks can be visualized. These different perspectives help the user to easier understand the relation between the control of a cell and the mechanical design, as well as the product design and the total system behavior. The proposed language is based on a formal model, thus formal verification, optimization and synthesis are available. This is necessary since it is hard to find errors in complex system Specifications. When implementing the control of manufacturing Operations, much of the code is related to supporting concerns like alarm handling, logging, user interface, etc. These parts tend to be hard to fully reuse and implement, since they are tangled with other functionalities, and are located at many places in the program. An aspect-oriented programming (AOP) approach is proposed, to reuse and implement these concerns. AOP is an emerging programming methodology in computer science, which helps the programmer by separating crosscutting and tangled concerns in a program. The approach is focused on how to adapt the AOP methodology for PLC program development, and how it can benefit the control design process.