105294
Structure-Preserving Binary Relations for Program Abstraction
An abstraction is a property-preserving contraction of a program's model into a smaller one that is suitable for automated analysis. An abstraction must be sound, and ideally, complete. Soundness and completeness arguments are intimately connected to the abstraction process, and approaches based on homomorphisms and Galois connections are commonly employed to define abstractions and prove their soundness and completeness.This paper develops Mycroft and Jones's proposal that an abstraction should be stated as a form of structure-preserving binary relation. Mycroft-Jones-style relations are defined, developed, and employed in characterizations of the homomorphism and Galois-connection approaches to abstraction.
7037195
Comparing Completeness Properties of Static Analyses and Their Logics
Static analyses calculate abstract states, and their logics validate properties of the abstract states. We place into perspective the variety of forwards, backwards, functional, and logical completeness used in abstract-interpretation-based static analysis by giving examples and by proving equivalences, implications, and independences. We expose two fundamental Galois connections that underlie the logics for static analyses and reveal a new completeness variant, O-completeness. We also show that the key concept underlying logical completeness is covering, which we use to relate the various forms of completeness.
42747855
Action Semantics-Directed Prototyping
We present a methodology for compiler synthesis based on Mosses-Watt's action semantics. Each action in action semantics notation is assigned specific ''analysis functions'', such as a typing function and a binding-time function. When a language is given an action semantics, the typing and binding-time functions for the individual actions compose into typing and binding-time analyses for the language; these are implemented as the type checker and static semantics processor, respectively, in the synthesized compiler. Other analyses can be similarly formalized and implemented. We show a sample language semantics and its synthesized compiler, and we describe the compiler synthesizer that we have developed.
7872163
Closed and Logical Relations for Over- and Under-Approximation of Powersets
We redevelop and extend Dams’s results on over- and under-approximation with higher-order Galois connections:
980049
An object-oriented framework for dynamically configuring extensible distributed systems
Developing extensible, robust and efficient distributed systems is a complex task. To help alleviate this complexity, we have developed the ADAPTIVE Service eXecutive (ASX) framework. ASX is an object-oriented framework composed of automated tools and reusable components. These tools and components help to simplify the development, configuration and reconfiguration of applications in a distributed environment. Using the ASX framework, the services in the applications may be updated and extended without modifying, recompiling, relinking or restarting the applications at run-time. This paper describes the features and object-oriented architecture of the ASX framework. It also describes how the ASX framework has been used to develop a highly modular, reusable and dynamically reconfigurable family of distributed system management applications.
602812
Autonomous behavior-based exploration of office environments
Besides safe motion control the gain of environmental knowledge is a key for a reliable home or office service robot. When being set into a completely unknown environment the robot has to be able to derive a certain abstract internal representation of this world without any user interaction. This knowledge enables the robot to know how to get from its actual place in one room to a target position in another room as a prerequisite for transportation tasks for example. In this context, the combination of a behavior-based motion control system and an abstract topological map based on geometric representations of rooms seems promising. As the concept of motion and exploration behaviors facilitates to compete with noisy sensor information and geometrically imprecise maps, it has been used to develop completely autonomous exploration strategies for deriving topological representations of common indoor environments. The only prescribed world knowledge is the fact that these environments are composed of rectangular entities (rooms) which are connected by openings (doors). The developed system has successfully been tested in simulation and reality.
6993185
Metric-driven analysis and feedback systems for enabling empirically guided software development
The authors summarize the goals of metric-driven analysis and feedback systems and describe a prototype system, Amadeus, which defines abstract interfaces and embodies architectural principles for these types of systems. Metric-driven analysis and feedback systems enable developers to define empirically guided processes for software development and maintenance. The authors provide an overview of the Amadeus system operation, including an example of the empirically guided process, a description of the system characteristics, an explanation of the system conceptual operation, and a summary of the users' view of the system. The centerpiece of the system is a pro-active server, which interprets scripts and coordinates event monitoring and agent activation. Amadeus provides an extensible framework for adding new empirically based analysis techniques.<<ETX>>
14353814
Patterns and performance of a CORBA event service for large-scale distributed interactive simulations
A process for curing acid-curable resins with photocatalyst compounds having the general formula: WHEREIN M = 0, 1 OR 2 AND P IS AN INTEGER FROM 1 TO 5 AND WHEREIN, WHEN P IS 1, R represents an alkyl or alkoxy group having at least 4 C-atoms, and when p>1, R represents alkyl or alkoxy groups having together at least 4 C-atoms. The photocatalyst which may be used is 2,2,2-trichloro-4'-tert-butylacetacetophenone. This compound may be prepared by chlorinating 4'-tert-butylacetophenone or by treating tert-butyl benzene in carbon disulfide with trichloroacetyl chloride or trichloroacetonitrile and aluminum chloride.
15679644
The J3 Process for Building Autonomic Enterprise Java Bean Systems
Autonomic computer systems aim to reduce the configuration, operational, and maintenance costs of distributed enterprise applications. This paper provides two contributions to the development of autonomic computing systems using Enterprise Java Beans (EJBs). First, we describe a model-driven development (MDD) tool that formally captures the design of EJB systems, their quality of service (QoS) requirements, and the autonomic properties that will be applied to the EJBs to support the rapid development of autonomic EJB applications. Second, we describe how this MDD tool can generate code to plug EJBs into a Java component framework that provides an autonomic structure to monitor, configure, and execute EJBs and their adaptation strategies at run-time