Software architectures must frequently evolve to cope with changing requirements, and this evolution often implies integrating new concerns. Unfortunately, existing architecture description languages provide little or...
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Software architectures must frequently evolve to cope with changing requirements, and this evolution often implies integrating new concerns. Unfortunately, existing architecture description languages provide little or no support for this kind of evolution. The software architect must modify the architecture manually, which risks introducing inconsistencies. In previous work, we have proposed the TranSATframework, which provides a pattern construct for describing new concerns and their integration into an existing architecture. As the interaction between the new concern and the existing architecture may be complex, it is essential that the framework ensure the coherence of the resulting architecture. In this paper, we introduce a language for specifying patterns and verifications that ensure that the concern represented by a pattern can be safely integrated into an existing architecture. The verifications comprise static verifications that check coherence properties before the architecture is modified and dynamic verifications that focus on the parts of the architecture that are affected by the pattern. As a result of these verifications, patterns can be provided as a commodity, such that a software architect can confidently apply a pattern obtained from a third-party developer
Optimistic type systems for logic programs are considered. In such systems types are conservative approximations to the success set of the program predicates. The use of logic programs to describe types is proposed. I...
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Optimistic type systems for logic programs are considered. In such systems types are conservative approximations to the success set of the program predicates. The use of logic programs to describe types is proposed. It is argued that this approach unifies the denotational and operational approaches to descriptive type systems and is simpler and more natural than previous approaches. The focus is on the use of unary-predicate programs to describe the types. A proper class of unary-predicate programs is identified, and it is shown that it is expensive enough to express several notions of types. An analogy with two-way automata and a correspondence with alternating algorithms are used to obtain a complexity characterization of type inference and type checking. This characterization is facilitated by the use of logic programs to represent types.< >
Aspect oriented programming (AOP) has been proposed as a new programming paradigm. The originality in AOP is the aspect, a single modularization unit for all those functionalities that were originally spread across se...
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Aspect oriented programming (AOP) has been proposed as a new programming paradigm. The originality in AOP is the aspect, a single modularization unit for all those functionalities that were originally spread across several modules and tangled with each other (called crosscutting concerns). Using an aspect, a crosscutting concern can be factored out into a single, separate unit. This paper summarizes a PhD thesis that presents an approach to automatize the migration of existing object oriented systems towards AOP. Different techniques are proposed to cope with the migration and assessed on a large software basis.
The object-oriented Robot Independent programming Environment (RIPE) is described. A system architecture based on hierarchies of distributed multiprocessors provides the computing platform for a layered programming st...
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The object-oriented Robot Independent programming Environment (RIPE) is described. A system architecture based on hierarchies of distributed multiprocessors provides the computing platform for a layered programming structure that models the application as a set of software objects. These objects are designed to support model-based automated planning and programming, real-time sensor-based activity, error handling, and robust communication. The object-oriented paradigm provides mechanisms such as inheritance and polymorphism which allow the implementation of the system to satisfy the goals of software reusability, extensibility, reliability, and portability. By designing a hierarchy of generic parent classes and device-specific subclasses which inherit the same interface, the Robot Independent programming Language (RIPL) is realized. Work cell tasks demonstrating robotic cask-handling operations for nuclear waste facilities are successfully implemented using this object-oriented software environment.< >
A fast, competitive CAD-procedure requires a high degree of automatization that also includes the generation of the test program. Starting with an analog test plan written by the user and a circuit description, a test...
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A fast, competitive CAD-procedure requires a high degree of automatization that also includes the generation of the test program. Starting with an analog test plan written by the user and a circuit description, a test program is generated automatically for analog circuits and for the analog part of hybrid circuits. The test program is synthesized from different, proven software modules. The additional hardware, which is required for the test, is realized in the standardized hardware modules.< >
The paper addresses the problem of automatically programming cooperative behaviors in a group of autonomous robots. The specific task that we consider here is for a group of distributed autonomous robots to cooperativ...
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The paper addresses the problem of automatically programming cooperative behaviors in a group of autonomous robots. The specific task that we consider here is for a group of distributed autonomous robots to cooperatively push an object toward a goal location. The difficulty of this task lies in that the task configurations of the robots with respect to the object do not follow any explicit, global control command, primarily due to certain modeling limitations as well as planning costs as in many real life applications. In such a case, it is important that the individual robots locally modify their motion strategies, and at the same time, create a desirable collective interaction between the distributed robot group and the object that can successfully bring the object to the goal location. In order to solve this problem, we have developed an evolutionary computation approach in which no centralized modeling and control is involved except a high level criterion for measuring the quality of robot task performance. The evolutionary approach to distributed robot behavioral programming is based on a fittest preserved genetic algorithm that takes into account the current positions and orientations of the robots relative to the object and the goal, and a weak global feedback on the collective task performing effect in relation to the goal if some new local motion strategies are employed by the robots.
Boeing engineers designed and implemented these algorithms using MOODS (Multibody On-Orbit Dynamics Simulation), a Boeing/NASA Ada non-realtime simulation running on a DEC Alpha platform in Boeing Tower 2 in Houston, ...
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Boeing engineers designed and implemented these algorithms using MOODS (Multibody On-Orbit Dynamics Simulation), a Boeing/NASA Ada non-realtime simulation running on a DEC Alpha platform in Boeing Tower 2 in Houston, Texas. The Ada flight software was then written in MatrixX superblocks on Hewlett Packard computers, using the MatrixX autocode capability to generate the Ada code. After Flight Stage 5A of the International Space Station (ISS), the Pointing and Support (P&S) subsystem is activated and provides the Guidance, Navigation, and Control (GN&C) interface for most of the other U.S. subsystems. P&S supplies state vector (ISS position and velocity), attitude, and attitude rate data to other ISS systems.
The increasing student-to-teacher ratio in university sector not only resulted in increased demand for automation of assignment marking and feedback but also raised concerns of increase in copying of assignments and c...
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The increasing student-to-teacher ratio in university sector not only resulted in increased demand for automation of assignment marking and feedback but also raised concerns of increase in copying of assignments and cheating. This paper considers a solution to this problem and offers an assignment individualization model and an assignment allocation model taking into account the risks and the costs involved. The models open way for minimizing teacher workload required to achieve a given acceptable level of plagiarism risk.
This research enable end users to create reusable new abstractions for data categories, thereby enabling them to automate these and other tasks by creating programs. "Tope," the Greek word for "place,&q...
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This research enable end users to create reusable new abstractions for data categories, thereby enabling them to automate these and other tasks by creating programs. "Tope," the Greek word for "place," is the name for such an abstraction in this research, since each abstraction corresponds to a data category that has a natural place in the problem domain (unlike float and int). For example, US phone number would be a *** tope implementation is a small package of executable software functions for recognizing, transforming, and equivalence-testing instances of a data category. The data model underlying a tope is a directed graph. Each graph node corresponds to a format, and each edge corresponds to a transformation between formats.
This paper describes a test-generation method that automatically creates efficient, high-quality vector sequences that catch ASIC pin faults at in-circuit board test. The method works with a sample IC. Simulation mode...
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This paper describes a test-generation method that automatically creates efficient, high-quality vector sequences that catch ASIC pin faults at in-circuit board test. The method works with a sample IC. Simulation models are not required.
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