Real Benefits of Active Caching in the WWW

We present our research on active caching in the WWW. We drew some key conclusions on the service properties and its significance, according to the results of our analysis of the WWW content. These conclusions include the percentage values of the potentially outdated Web content in the overall Web content after an object`s lifetime has passed. This paper provides reasons for using active cachin

Some recommendations on building proxy caching service

In this paper, we present our research on WWW caching proxies. We drew some key conclusions on the service properties and caching policies, according to the results of our analysis of caching proxies. These conclusions include our recommendations on cache configuration and illustrate how choosing cache scenarios depends on the different requirements requested by the cache manager and different network conditions

"RM-ODP part 2: Foundations" in Alloy

This paper presents the Alloy code for the formalization of “RM-ODP part 2: Foundations”. The formalization is defined and explained in the separate work

Conceptual Modeling of Complex Systems Using an RM-ODP Based Ontology

The development of business and information systems requires a significant amount of modeling. The current modeling languages and tools have difficulties supporting the modeling of systems spanning through multiple organizational levels. The use of inadequate modeling abstractions is one of the important causes for these difficulties. This paper proposes an ontology that defines the concepts needed for object-oriented modeling and gives a graphical example. The ontology is based on RM-ODP and relies on Constructivism and System Theory. The proposed ontology allows the definition of development methods, modeling languages and tools that are applicable to complex systems. This can lead to significant productivity improvements in the business and software development communities

Application of Information Management with Meeting Automation Tool

This paper presents results of our research that targets the improvement of workgroup efficiency with technological support for the management of group-related information. We built a software tool that enables all the people in a workgroup to work with information related to their common projects. We present our solution: the theoretical concepts that are implemented, its structure, functionality and architecture

A Metamodel for the Unified Modeling Language

Nowadays models, rather than code, become the key artifacts of software development. Consequently, this raises the level of requirements for modeling languages on which modeling practitioners should rely in their work. A minor inconsistency of a modeling language metamodel may cause major problems in the language applications; thus with the model driven systems development the solidness of modeling languages metamodels becomes particularly important. In its current state the UML metamodel leaves a significant area for improvement. We present an alternative metamodel that was inspired by the RM-ODP standard and that solves the problems of UML. RM-ODP was mentioned in UML specifications as a framework that has already influenced UML. Our metamodel was formalized, thus its resulting models can be simulated and checked for consistency. So, our proposed solution with constructive potential towards improvement of the UML metamodel, may have a significant practical impact on the UML specifications

The Role of Tarski’s Declarative Semantics in the Design of Modeling Languages

This paper focuses on Tarski`s declarative semantics and their usefulness in the design of a modeling language. We introduce the principles behind Tarski`s approach to semantics and explain what advantages this offers in the context of modeling languages. Using sentential logic we demonstrate the necessity and sufficiency of Tarski`s semantics for effectively addressing several issues that arise in the design of modeling languages. We explain what role Tarski`s semantics play in the organization of a modeling language. This role is compared to the analogous roles of denotational semantics and operational semantics. We show that in the context of a modeling language Tarski`s semantics are complementary to the other two kinds of semantics. The paper is intended to assist modeling language researchers and designers, particularly in connection with the UML - a language that in its current form does not feature Tarski`s declarative semantics

A metamodel for the Unified Modeling Language: critical analysis and solution

Nowadays models, rather than code, become the key artifacts of software development. Consequently, this raises the level of requirements for modeling languages on which modeling practitioners should rely in their work. A minor inconsistency of a modeling language metamodel may cause major problems in the language applications; thus with the model driven systems development the solidness of modeling languages metamodels becomes particularly important. At its current state the UML metamodel suggests a significant area for improvement. In this work we present an alternative metamodel that was inspired by RM-ODP standard and that solves the problems of UML. RM-ODP was mentioned in UML specifications as a framework that has already influenced UML. Our metamodel was formalized, thus its resulting models can be simulated and checked for consistency. So, our proposed solution carrying a constructive potential towards improvement of the UML metamodel, may have a real practical impact on the UML specifications

A Formal Foundation of the RM-ODP Conceptual Framework

This paper presents an approach for formalizing the RM-ODP (Reference Model for Open Distributed Processing), an ISO and ITU standard. The goal of this formalization is to clarify the RM-ODP modeling framework to make it more accessible to modelers such as system architects, designers and implementers, while opening the way for the formal verification of RM-ODP models, either within an ODP viewpoint or across multiple ODP viewpoints. The result of this work is a consistent formal representation of clauses 5, 6, 8 and 9 of part 2 of RM-ODP in their interrelations, which while being officially declared as one of its goals is currently missing in the standard. Our formalization is based on set theory and the classical predicate logic, and is expressed in the Alloy language