Monografias em Ciência da Computação

1998

ABSTRACTS

Departmento de Informática 
Pontifícia Universidade Católica do Rio de Janeiro - PUC-Rio
Rio de Janeiro - Brazil

This file contains a list of the technical reports of the Departmento de Informática, Pontífícia Universidade Católica do Janeiro - PUC-Rio, Brazil, which are published in our series Monografias em Ciência da Computação (ISSN 0103-9741), edited by Prof. Carlos Lucena. Please note that the reports not available for download are available in their print format and can be obtained via the e-mail below.

For any questions, requests or suggestions, please contact:
Rosane Castilho bib-di@inf.puc-rio.br

Last update: 18/DECEMBER/2003

INDEX 

[MCC01/98]
VELOSO, P.A.S.; VELOSO, S.R.M.; FIADEIRO, J.L. On families of specifications over a II-Institution: modularity in formal stepwise development. 30 p. Eng. E-mail: bib-di@inf.puc-rio.br

Abstract: Families, of components and/or versions (of programs or specifications), appear naturally in software development. We examine some issues in their setpwise development, such as modularity, interactions between selections of members, control of refinements and parallel elaboration. We focus on implementations of families of specifications and the use of labels to tag their members and their development paths. The concept of implementation in modular development of programs from formal specifications, as an interpretation into a conservative extension, is generalised to labelled families and formulated categorically. We show that this category has pushouts and products and these constructions preserve properties used in stepwise development.


[MCC02/98]
MILIDIU, R.; PESSOA, A.A.; LABER, E.S. A space-economical algorithm for minimum-redundancy coding. 22 p. Eng. E-mail: milidiu@inf.puc-rio.br

Abstract: No English abstract provided


[MCC03/98]
RODRIGUEZ, N.; IERUSALIMSCHY, R.; CERQUEIRA, R. Dynamic configuration with CORBA components. 15 p. Eng. E-mail: noemi@inf.puc-rio.br

Abstract: Most existing support for dynamic reconfiguration assumes that component interfaces specify input and ouput channels. The CORBA model, however, supports specifically a client-server architecture, with component interfaces describing only the provided services. Besides, the existing bindings for CORBA, based on static stubs, impose considerable difficulties on dynamic configuration. This paper investigates the use of the interpreted language Lua as a tool for dynamic configuration applications using CORBA components.


[MCC04/98]
LAUFER, C.; FUKS, H.; LUCENA, C.J.P. Rio Internet TV AulaNet: vídeo conferência em Web-based learning. 14 p. Eng. E-mail: hugo@inf.puc-rio.br

Abstract: This paper presents the results of an experiment using videoconference as a teaching resource in distance courses. CU-SeeMe and Real technology were tested for transmitting lessons live and recording lessons for asynchronous attendance. The results were assessed for later use in AulaNetTM, a tool for web-based learning.


[MCC05/98]
CHOREN, R.; BLOIS, M.; FUKS, H. QUEST- an assessment tool for Web-based learning. 7 p. Eng. E-mail: hugo@inf.puc-rio.br

Abstract: The internet has great potencial for education purposes. In 1997, the Software Engineering Laboratory at PUC-Rio implemented a first version of AulaNetTM , a web-based educational environment. This year, some of the teaching staff will be using this environment to offer regular term disciplines through the Web. This paper introduces Quest, the quiz generator and assessment tool incorporated into AulaNetTM to provide the means to support educational assessment through the Web.


[MCC06/98]
BLOIS, M.; CHOREN, R.; FUKS, H. CLEW - a cooperative learning environment for the Web. 7 p. Eng. E-mail: hugo@inf.puc-rio.br

Abstract: This work outlines CLEW a collaborative learning environment for the Web. The project combines MUD, workflow and educational concepts like Constructivism in a learning environment, where students actively participate in the learning process.


[MCC07/98]
BREITMAN, K.; LEITE, J.C.; FINKELSTEIN, A. The world's a stage: a survey on requirements engineering using a real-life case study. 46 p. Eng. E-mail: julio@inf.puc-rio.br

Abstract: In this report we present an analysis of a case study drawn from a real life setting, namely the London Ambulance Service System (LAS). We depart from a very detailed description of a real system that had problems and point out to specify research results that could have been applied in order to minimize some of them. This case study provides a unique opportunity to look at the results from research on the Requirements Engineering field through the prism of a real-life case study. In this light, a contribution of this work is showing the applicability of research findings in a real life setting. A natural outcome of our effort is a set of arguments sustaining the cause for Requirements Engineering research. This report is mostly based on the case study information provided by the Report of the Inquiry of the LAS, that provides a detailed account of the development and implementation of a real system and its surroundings. We survey some of the most recent methods and techniques and, at the same time, point out to real situations where they could have been used and, perhaps minimized some of the perceived problems. The main contribution of this paper is pointing out situations in which results from recent research efforts in Requirements Engineering could, to some degree, be put to practice. As researchers, one of our major concerns is recognizing problems in real world practice and and identifying candidates for further research.


[MCC08/98]
SCHWABE, D.; PONTES, R.A. OOHDM-WEB: Rapid prototyping of hypermedia applications in the Web. 15 p. Eng. E-mail: schwabe@inf.puc-rio.br

Abstract: This paper presents OOHDM-WEB, an environment allowing rapid prototyping of hipermedia applications designed using OOHDM in the WWW. This environment allows direct maping of navigation and interface constructs of OOHDM into a library of fucntions in the CGI scripting environment CGI-LUA, extended with the DB-LUA package. This environment allows implementation of hypermedia applications as CGI scripts that produce dynamically generated pages, whose contents are fed from a database and integrated with pre-defined templates.


[MCC09/98]
SCHWABE, D.; ROSSI, G.; GARRIDO, A. Designing web information systems. 19 p. Eng. E-mail: dschwabe@inf.puc-rio.br

Abstract: This paper characterizes Web Information Systems (WIS), identifying distinguishing features and discussing their design requirements. Next, it presents the notion of Design Patterns, and shows how they can be applied to the design of WIS, drawing examples from sites in the WWW.


[MCC10/98]
BARROSO, N. G.; SCHWABE, D. Projeto de navegação em aplicativos hipermídia orientado ao usuário. 19 p. Port. E-mail: dschwabe@inf.puc-rio.br

Abstract: This paper describes a user centered method for navigation design in hypermedia applications. The  proposed approach extendes the Navigational phase of OOHDM with the use of scenarios. This allows the reuse by less experienced designers of design knowledge, gathered by more experienced ones, resulting in a more systematic method. The method's effectiveness has been exercized in designing the navigation of real life hypermedia application in the WWW, which allowed a better characterization of such applications with respect to other hypermedia applications. A second consequence has been the enrichment of OOHDM, making it more suitable for representing solutions for the WWW.


[MCC11/98]
SCHWABE, D.; ROSSI, G.; GARRIDO, A. Reutilização de projetos em aplicação hipermídia. 13 p. Port. E-mail: dschwabe@inf.puc-rio.br

Abstract: No English abstract provided.


[MCC12/98]
MOURA, A.L.; ISHIKAWA, E.; LIMA, M.E.; RODRIGUEZ, N. Aplicações de gerência extensíveis. 19 p. Port. E-mail: noemi@inf.puc-rio.br

Abstract: This paper proposes an environment for the development of network management applications. This environment is based on Lua, which is an interpreted language, and on a set of libraries. The paper gives special attention to the LuaMan library, which was developed for the specific needs of network management. Applications written on this platform can be dynamically extended; this allows new functionality to be added without the need of recompilation. The paper also describes a web based management application which was built using the proposed environment. 


[MCC13/98]
CRESPO, S.; FONTOURA, M.F.M.C.; LUCENA, C.J.P. A framework development method using viewpoints and the views - a relationship in the OO design. 10 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: In this paper we describe a viewpoint-based design method for framework development. This method uses the concept of viewpoints and the views-a relation in object-oriented design to guide the designer on the identification of hot-spots in the structure of the framework. Case studies have shown that high levels of software reuse can be achieved through the use of object-oriented frameworks. Although, analysis and design methods such as design patterns, meta-object protocol, refactoring, class reorganization, behavior of modification for framework, have been proposed to support frameworks development there are still problems related to this topic associated with ease of reuse. The viewpoint-based development method appears to be a very succesful approach from the point of view of component reuse.


[MCC14/98]
CRESPO, S.; FONTOURA, M.F.M.C.; LUCENA, C.J.L. AulaNetTM: an object-oriented environment for Web-based education. 16 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: As yet there are no specialists in the application of information technology to education and training. However, this is one of the fastest growing areas on the Internet, due to the recent perception of the enormous potential for the use of Web resources for this purpose. This potentiality has attracted the attention of researchers in industry and the academic world, which are currently developing various models and products for Web-based education and training. In this paper we present AulaNet, an environment for the creation and maintenance of Web-based courses designed for the layman, highlighting its architecture and design model. We also compare AulaNet to other Web-based education (WBE) environments.


[MCC15/98]
VELOSO, P. Some constructions on categories related to fork and projection algebras. 18 p. Eng. E-mail: bib-di@inf.puc-rio.br

Abstract: A relational algebra can be expanded along two axes: by a binary operation or by a pair of constant elements. We examine some natural constructions between such expansions of relational algebras, which provide functors. These functors preserve some categories related to fork algebras and truly projective algebras and establish isomorphisms between some of them, in particular between fork algebras and truly projective algebras.


[MCC16/98]
MILIDIÚ, R.L.; LABER, E.S.; PESSOA, A.A. A work efficient parallel algorithm for constructing Huffman codes. 12 p. Eng. E-mail: milidiu@inf.puc-rio.br

Abstract: No English abstract provided.


[MCC17/98]
ALENCAR, P.S.C.; COWAN, D.D.; CRESPO, S.; FONTOURA, M.F.M.C.; LUCENA, C.J.P. Using viewpoints to drive a conceptual model for web-based education environments. 24 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: This paper proposes a conceptual model for Web-Based Education (WBE) environments that is implemented through an object-oriented framework. We also define a domain-specific language (DSL), which is used to instantiate the framework, as part of the model. The process of defining this model is based on viewpoints and on our viewpoint-based development method for object-oriented frameworks. The domain analysis was developed through the study of various WBE environments, which were used as viewpoints of this type of environment. A description of the development method is presented to clarify its application in the elicitation and design processes. The object models of the analyzed environments are also presented. The resulting conceptual model is currently being implemented in a visual programming language and will be used for the generation of different WBE environments.


[MCC18/98]
ALENCAR, P.S.C.; COWAN, D.; CRESPO, S.; FONTOURA, M.F.M.C.; LUCENA, C.J.P. OwlNet: an object-oriented environment for WBE. 11 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: The paper presents the design and the architecture of a new Web-Based Education (WBE) environment. This environment is based on the integration of two other WBE's applications: AulaNetTM and LiveBOOKs. Here we present the main features and the architecture of those two environments to justify our motivation for the development of OwlNet. Then we show the architecture and features of this new environment.


[MCC19/98]
BRAGA, C.O.; STAA, A.v.; LEITE, J.C.S.P. Documentu: a flexible architecture for documentation production based on a reverse engineering strategy. 22 p. Eng. E-mail: arndt@inf.puc-rio.br

Abstract: Good documentation is essential to the production and evolution of quality software. Based on a survey on program documentation, we propose a documentation architecture that aims to fulfill several requirements of an ideal solution. The architecture integrates a powerful transformation system (Draco-PUC) and a versatile CASE tool (Talisman) in order to produce documents using reverse engineering strategies. We have implemented such approach in a prototype tool called Documentu, which uses a database to store system wide information and uses a standard HTML hypertext browser to help the access and navigation of system documentation. The prototype was used on a large scientific system that belongs to an oil company, with positive results.


[MCC20/98]
LABER, E.S.; MILIDIU, R.L.; LUCENA, C.J.P. Improving the complexity of the WARM-UP algorithm. 17 p. Eng. E-mail: milidiu@inf.puc-rio.br

Abstract: No English abstract provided.


[MCC21/98]
CARVALHO, S.E.R. Mediator-based object-oriented frameworks. 11 p. Eng. E-mail: bib-di@inf.puc-rio.br

Abstract: The pursuit of software reuse through frameworks shows promise in the object orientation paradigm. This paper presents a recursive architecture for frameworks, based on the Mediator pattern. Domain entities and relationships are represented by mediators having, as components, classes implementing all aspects that entities and relationships must offer to framework instantiors.  These mediators can in turn de used as mediator components. Also presented are special design and language features that fully realize the benefits of this architecture, as well as an indication of how to construct mediator-based frameworks.


[MCC22/98]
PORTO, F.A.M.; SILVA, M.J.V.; CARVALHO, S.E.R. Object life-cycles in active relational databases. 11 p. Eng. E-mail: bib-di@inf.puc-rio.br

Abstract: One of the biggest problems that object-oriented developers face today is having to integrate at the enterprise level, object-oriented applications with widely applied and quality active relational databases. This paper focuses on the issues of mapping object dynamic behavior into active relational databases. We present a technique for expanding active relational databases with object-oriented behavior semantics, extrated from state transitions diagrams expressing object life cycles. We consider states as first class objects, and discuss state class and event inheritance.


[MCC23/98]
LIMA, M.J.D.; CARVALHO, S.E.R.; SILVA, M.V. An object-oriented framework for pattern assistants. 20 p. Eng. E-mail: bib-di@inf.puc-rio.br

Abstract: Software patterns, at the architecture, design and language levels, are finding their way in object-oriented communities. New patterns are constantly being published, spanning different domains, and although few can be considered essential, to keep of new developments is not easy. To help designers cope with this difficulty, and to speed up and improve the quality of systems, automated development tools should include pattern facilities, for example to assist designers in the selection and detailing of patterns adequate to their development problems. This paper presents a domain and language-independent object-oriented framework for pattern assistants, constructed with the aid of well-known design patterns.


[MCC24/98]
ANDREATTA, A.A.; CARVALHO, S.E.R.; RIBEIRO, C.C. An object-oriented framework for local search heuristics. 13 p. Eng. E-mail: celso@inf.puc-rio.br

Abstract: In the study of heuristics for combinatorial problems, it is often important to develop and compare, in a systematic way, different algorithms, strategies, and parameters for the same problem. This comparison is often based not only by different implementation languages, but also by different architectures. This paper proposes a framework, described using design patterns, modeling different aspects involved in local search heuristics, such as algorithms for the construction of initial solutions, methods for neighborhood generation, and movement selection criteria. Using this framework we fix a basic architecture and thus increase our ability to construct and compare heuristics.


[MCC25/98]
CARVALHO, S.E.R.; LEITE, J.C.S.P. Module interconnection features in object-oriented development tools. 12 p. Eng. E-mail: julio@inf.puc-rio.br

Abstract: The black-box reuse of library classes in the construction of an object-oriented (OO) application is difficult: the principle of information hiding may be violated if classes must know thier patterns, and code must be typically rewritten. One of the possible ways to increase class decouping and thus reuse is to employ interconnection languages to describe OO architectures. In this paper we present a decouping paradigm for individual classes or class collections that facilitates reuse, introducing interconnection features at the design and programming levels. We give examples in a new, second generation object-oriented development system, using asynchronous messages sent to generically identified receivers.


[MCC26/98]
SILVA, M.J.V.; CARVALHO, S.E.R.; KAPSON, J. Patterns for layered object-oriented applications. 10 p. Eng. E-mail: bib-di@inf.puc-rio.br

Abstract: Three-layered architectures (presentation, business and persistence levels, for example) are sometimes recommended when developing business-related object-oriented applications. Using the increasingly popular fourth generation languages, however, layering is difficult: business rules are usually embedded in user interfaces, which may also directly access databases. In this paper, we present three patterns useful in the construction of object oriented applications accessing relational databases via fourth generation languages.


[MCC27/98]
COSTA, H.A.X.; MAFFEO, B.; SANCHEZ, M.L.A. SAME - Protótipo de um sistema para apoio a modelagem da essência baseado no reúso em larga escala. 17 p. Port. E-mail: maffeo@inf.puc-rio.br

Abstract: This work describes a protype intended to be an instrument for the elicitation of the desired functionality for a Conceptual Modeling Environment to support the creation of the Essence Model for an information system. The protype is user friendly and was developped following a large scale reuse strategy, based on commercially available application software. This strategy was intended to provide an experimental test for this kind of reuse which, suitably adapted, can be the basis for a generic method for rapid prototyping of information systems.


[MCC28/98]
BRAGA, C.O.; FONTOURA, M.F.M.C.; LUCENA, C.J.P.; MOURA, L.M. Using domain specific languages to instantiate OO frameworks. 21 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: Prior research has shown that high levels of software reuse can be achieved through the use of object-oriented frameworks. An object-oriented framework captures the common aspects of a family of applications The framework also captures the design experience in producing the application, and thus, allows the designers and implementers to reuse this experience at the design and code levels. Despite of being a powerful design solution, frameworks are not always easy to use. This paper describes a technique that captures domain concepts in domain specific languages (DSL) to help the framework user to create a specific application in an easier way, without worrying about implementation decisions and remaining focused on her problem domain. The specification written in the DSL is then translated to the framework instantiation code using a transformational system.


[MCC29/98]
ROSSETI, I.C.M.; RODRIGUEZ, N. Balanceamento de carga em uma implementação distribuída do problema dos N-Corpos. 44 p. Port. E-mail: noemi@inf.puc-rio.br

Abstract: Load balancing has become a fundamental factor in the effective use of distributed-memory environments for parallel computation. This paper studies the application of load-balancing algorithms to a parallel simulation of the N-body problem. The Matrix Iterative Model is used as an unifying basis for the implementation of a load-balancing library. Experimental design and analysis techniques are used to examine application performance with the use of this library.


[MCC30/98]
VELOSO, P.A.S.; HAEUSLER, E.H. Towards a methodology for extracting programs and solutions from constructive proofs. 21 p. Eng. E-mail: hermann@inf.puc-rio.br

Abstract: We introduce a general methodology for extracting problem-solving programs from constructive derivations, which is suggested by a problem-theoretic interpretation of intuitionism and by Martin-Lof's (ITT) Intuitionistic Type Theory. This methodology comes from a formal system related to intuitionism which incorporates two key ideas, namely manipulations with derivations and the possibiblity of distinct treatments for sorts and formulas, in contrast with others based directly on ITT. Moreover, this methodology can be shown to be sound (correct) and complete (non-obtrusive). We use some examples to introduce the main ideas of this methodology and illustrate its usefulness.


[MCC31/98]
CRESPO, S.; FONTOURA, M.F.M.C.; LUCENA, C.J.P. Ambientes para educação baseada na Web e o modelo IMS/EDUCOM. 19 p. Port. E-mail: lucena@inf.puc-rio.br

Abstract: This paper proposes a conceptual model for Web-based education environments (WBE), which was developed through a case study of various existent environments. This conceptual model is used as a basis for the comparison of the concepts and functionaly of the existent environments. The proposed conceptual model is compatible with the EDUCCOM/IMS platform, allowing content interoperability for the generated environments. The model implementation is made through an object-oriented framework and a domain specific language.


[MCC32/98]
FRANCA, L.P.A.; STAA, A.v.; LUCENA, C.J.P.L. Medição de software para pequenas empresas: uma solução baseada na Web. 23 p. Port. E-mail: arndt@inf.puc-rio.br

Abstract: The use of metrics is directly related to software process improvement. Measurement programs should be flexible and easily adaptable to the features of each organization. Moreover, in the context of small software business, measurement should be feasible in spite of the lack of resources. In order to produce measurement systems that face the needs of the dynamic reality of small business and support an incremental evolution, we have develped a meta-system that is capable of instatiating suitable measurement systems to each organization. The system generation is based on the generic measurement model stored in software engineering meta-environment. The measurement systems generated are Web-based applications.


[MCC33/98]
FONTOURA, M.F.M.L.; HAEUSLER, E.H.; LUCENA, C.J.P. The hot-spot relationship in OO framework design. 10 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: The generalization from viewpoints is a key design concept in our framework design method. However, viewpoints are not generally designed to be flexible applications. The hot-spot relationship is a new relationship in object-oriented design that helps in this generalization, providing the flexibility properties in the derivation of the framework kernel. This paper presents our viewpoint-based framework design method, highlighting the role of the hot-spot relationship. Object calculus is used to formalize the relationship and prove that its semantics and prove that its semantics is provided by the design pattern essentials.


[MCC34/98]
CRESPO, S.; FONTOURA, M.F.M.C.; LUCENA, C.J.P.; MOURA, L.M. ALADIN: an architecture for learningware applications design and instantiation. 18 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: This paper presents an abstract software Architecture for Learningware Application Design and Instatiation (ALADIN), which is basedon a conceptual model for Web-based education (WBE) environments. ALADIN is designed through a combination of architectural patterns and implemented through an object-oriented framework and domain-specific languages (DSLs). The DSLs are used for framework instatiation to help the framework user to create a specific application in an easier way, without worring about implementation decisions and remaining focused on the problem domain. The specification written in the DSLs are then translated to the framework instantiation code using a transformational system. Utilization examples showing how WBE environments can be implemented with ALADIN are also shown.


[MCC35/98]
FONTOURA, M.F.M.C.; HAEUSLER, E.H.; LUCENA, C.J.P. A framework design and instantiation method based on viewpoints. 36 p. Eng. E-mail: lucena@inf.puc-rio.br

Abstract: This paper describes a viewpoint-based design and instantiation method for object-oriented frameworks. Case studies have shown that high levels of software reuse can be achieved through the use of object-oriented frameworks. Although analysis and design methods, such as design patterns, meta-object protocol, refacturing, class organization, and behavior of modification for framework have been proposed to support framework development, there are still problem related to this approaches. The method proposed in this paper uses the concept of viewpoints and the hot-spot relationship in object oriented design to guide the designer on the identification of hot-spots in the structure of the framework and in the generation of the design patterns that implement each hot-spot. This paper also shows how the use of domain specifc languages (DSLs) can help in the framework instantiation process. The domain specific language captures domain concepts and helps the framework user to create an application in an easier way, without concerning for implementation decisions while remaining focused on the problem domain. The specification writen in the DSL in then translated to the framework instantiation code through the use of transformational systems. A case study in the Web-based Education domain is presented to illustrate the method utilization. A formal specification of the design method using Z specification language is also presented. Through this formalization it is possible to precisely describe each method's step and to highlight its most important properties.


[MCC36/98]
ALBUQUERQUE, A.L.P. Texturas em computação gráfica. 21 p. Port. E-mail: bib-di@inf.puc-rio.br

Abstract: Texture values can be produced by space-filling functions f(x,y,z) or 2D functions f(x,y). Different ways for applying these functions lead to interesting results. This work intends to discuss the synthesis of texture for representing realistic images. Many concepts and different techniques for texturing are examined and some images - obtained as a result of the implementation of some functions - are shown.


[MCC37/98]
PAIVA, A.C.; RODRIGUEZ, N.; GATTASS, M. Técnicas paralelas de rendering. 79 p. Port. E-mail: noemi@inf.puc-rio.br

Abstract: This work surveys the parallel techniques applied to the rendering process. The basic parallel concepts are revised from the point of view of the rendering process, and some software and hardware implementations are discussed.


[MCC38/98]
VIDAL, M.E.F.; MAFFEO, B. Método para mapeamento e avaliação de processos organizacionais. 23 p. Port. E-mail: maffeo@inf.puc-rio.br

Abstract: This paper presents a method to map and to evaluate organizational processes, to be employed in distinct phases of a reengineering initiative.According to this method, the definition of a new design for the process to be innovated begins with the creation of the model of the essence of the socio-technical system responsible for the process execution. This model is a conceptual tool of Software Engineering used to represent what the system is expected to do, regardless to how the system will be implemented by means of a specific technological alternative. Conceptual tools of Software Engineering are also used to represent the current and innovated process design. The later must also be compared both quantitatively and qualitatively to the former order to evaluate its viability and opportunity, as well as the cost-effectiveness of the reengineering initiative. The evaluation proposed is to be supported by a commercial software tool widely used in project management. The method was tested in a case study for the goods' reception process of a department store. It was necessary to marginally extend and adapt the representation languages used to model the essence and to specify the design of the process in order to represent some specific features of organizational processes.


[MCC39/98]
CRESPO, S.; LUCENA, C.J.P.; STAA, A.v. Um meta-ambiente para suporte a construção sistemática de frameworks. 13 p. Port. E-mail: lucena@inf.puc-rio.br

Abstract: In this paper we describe an environment that supports a design method for object oriented software in WEB, combining Frameworks and Design Patterns. This environment uses the concept of viewpoints and views-a relation in object-oriented design to guide the designer when identifying hot-spots in the structure of the framework. Case studies have shown that high levels of software reuse can be achieved through the use of object-oriented frameworks. It is possible to capture the common aspects revealed through the design experience acquired while designing a family of application. Although analysis and design methods such as design patterns, meta-object protocol, refactoring, class reorganization, behavior of modification for framework, have been proposed to support frameworks there are still problems related to framework creation. The use of an environment that gives support to the veiw-point concept and the flexibility relationships, hot-spot and of reuse by a view-a, proving a promising approach for this kind of problem, and an extension for the method in its applicability in order to accomplish reuse in large scale.


[MCC40/98]
CARVALHO, S.; LERNER, S.; LIFSCHITZ, S. An application framework or the parallel join operation in database systems. 17 p. Eng. E-mail: sergio@inf.puc-rio.br

Abstract: We propose an object-oriented framework modeling one of the most frequently accessed and costly operations in parallel Database Systems: the parallel join. By incorporating the behavior of known algorithms and allowing the introduction of new ones, the framework can be used to compare algorithms and to determine the execution scenario an algorithm is best suited for. The framework independently captures a great variety of issues, such as different target parallel architectures, different load balancing procedures, and different synchronism disciplines. The proposed framework includes the classification of related algorithms into families, suggesting a taxonomy for join operation algorithms.


[MCC41/98]
PORTO, F.A.M.; SILVA, M.J.V.; CARVALHO, S.R.; MELO, R.N. Persistent object synchronization with active relational databases. 14 p. Eng. E-mail: rubens@inf.puc-rio.br

Abstract: One of the most common client/server architectures in enterprise systems today is the combination of object-oriented applications with active relational database systems. With this combination, developers have to overcome a difficult problem: the impedance mismatch between the object-oriented and the relational models. To date, there are several incomplete approaches for describing the integration of static and dynamic aspects of objects into active relational databases. For example, in a previous paper, we proposed a technique for mapping the dynamic behavior of objects into active relational databases, using database triggers and stored procedures. However, an important issue missing from all these approaches is the synchronization between server tuples and client-cached objects. This paper extends our previous one, by providing an architecture based on a replication strategy that maintains server tuples and client-cached objects synchronized. This architecture automatically updates client-cached object versions when their corresponding server database tuples are updated.


[MCC42/98]
CRESPO, S.; LUCENA, C.J.P.; STAA, A.v. FrameConstructor: uma ferramenta para suporte à construção sistemática de frameworks. 45 p. Port. E-mail: lucena@inf.puc-rio.br

Abstract: In this paper we describe an environment supports a design method for object oriented software in WEB, combining Frameworks and Design Patterns. This environment uses the concept of viewpoints and the views-a relation in object-oriented design to guide the designer when identifying hot-spots in the structure of the framework. Case studies have shown that high levels of software reuse can be acheived through the use of object-oriented frameworks. It is possible to capture the common aspects revealed through the design experience acquired while designing a family of application. Although analysis and design methods such as design patterns, meta-object protocol, refactoring, class reorganization, behavior of modification for framework, have been proposed to support frameworks there are still problems related to framework creation. The use of an environment that gives support to the view-point concept and the flexibility relationships, hot-spot and of reuse by view-a, providing a promising approach for this kind of problem, and an extension for the method in its applicability in order to accomplish reuse in large-scale.


[MCC43/98]
LUCENA, C.J.P.; FUKS, H.; MILIDIU, R.; LAUFER, C.; BLOIS, M.; CHOREN, R.; TORRES, V.; DAFLON, L. AulaNet: ajudando professores a fazer seu dever de casa. 12p. Port. E-mail: lucena@inf.puc-rio.br

Abstract: In this paper we present AulaNet, an environment for the creation and maintenance of Web-based courses designed for the layman. Why the layman? Because the teacher is the one who needs help in the task of creating a Web-based course. AulaNet separates content from navigation and relieves teachers from the Internet programming burden. It differs from other Web-based instruction environments because it lacks the physical elements of the traditional school which are ever present in most of the other environments.


[MCC44/98]
SCURI, A.E.; SZENBERG, F.; SOUZA, C.S. Estudo de usabilidade do Microsoft Visual C++. 12 p. Port. E-mail: clarisse@inf.puc-rio.br

Abstract: This work atempts to identify the major usability problems related with Microsoft Visual C++, regarding to begginers, intermediate and advanced users. We organize a test that follows a script, common to all user classes.The test was recorded with Microsoft Camcorder in Windows 95, but some important user actions were manual registered. At the end of the test, every user answered a questionnare, to show us the applications facilities and dificulties. The results are presented in tables and in a descriptive conclusion.


[MCC45/98]
CARNEIRO, M.M.; VILAIN, P.; RENTERIA, R.P. Avaliação da usabilidade do programa para Imposto de Renda (IRPF98). 53 p. Port. E-mail: bib-di@inf.puc-rio.br

Abstract: This work presents the usability analysis of IRPF98, which is the Brazilian software for the declaration of income taxes by individuals. At first, the evaluators tried to identify potential problems mainly related to usability. Then, some of these problems were chosen considering their importance and time constraints of this work. A test was defined for each problem selected. Before applying the tests to the users, a pilot study was performed, thus resulting in some changes in the original tests. Three evaluators applied the final tests to a group of fifteen users. The results were used to verify the hypothesis defined by the evaluators.


[MCC46/98]
BLOIS, M.; CHOREN, R. Avaliação sobre a interface do White Pine CU-SeeMe, v. 3.1. 35 p. Port. E-mail: bib-di@inf.puc-rio.br

Abstract: This work presents a White Pine CU-See-Me v.3.1 interface evaluation process. It identifies some interface problems concerning its operation and interface elements through the observing and minitoring and user's opinions methods. At the end, we show the software interface quationable points and make suggestions for its improvement.


[MCC47/98]
GUELL BARROSO, N.; SOUSA, M.V.V. Teste de usabilidade de software - um estudo de caso. 41 p. Port. E-mail: bib-di@inf.puc-rio.br

Abstract: [The report is not available]

[MCC48/98]
CIARLINI, A.E.M.; FURTADO, A.L. The plan recognition / plan generation. 13 p. Eng. E-mail: furtado@inf.puc-rio.br

Abstract: Any computerized application-domain environment equipped with a Log of the execution of predefined operation can be regarded as a repository of narratives concerning the activities observed in the mini-world of interest. The analysis of these narratives leads to the construction of a library of typical plans, which can be used by Plan-recognition / Plan-generation algorithms to help prediction, decision making and the adoption of corrective measures with respect to ongoing activities. The proposed goal-oriented paradigm emerges as a promising research line to help understanding, and hence better modelling and using, so diverse domains as business information systems, literacy genres of narratives, and object-oriented software based on frameworks.


[MCC49/98]
PLASTINO, A.; RIBEIRO, C.C.; RODRIGUEZ, N.L.R. Uma taxonomia de algoritmos de balanceamento de carga para aplicações SPMD. 33 p. Port. E-mail: celso@inf.puc-rio.br

Abstract: We propose a taxonomy of load balancing strategies for SPMD (Single Program, Multiple Data) parallel applications. This taxonomy leads to a classification of local balancing algorithms designed for data parallel applications in MIMD architectures. This classification allows more thorough comparison studies of different load balancing techniques, helping application programmers in the task of identifying the most suitable strategy for some given SPMD application under development.


[MCC50/98]
CYSNEIROS, L.M.; MACEDO-SOARES, T.D.L.v.A.; LEITE, J.C.S.P. Using ISO 9000 to elicit business rules. 12 p. Eng. E-mail: julio@nf.puc-rio.br 

Abstract: Business rules have been largely used in database modeling and more recently in the field of information technology, but rarely in requirements engineering. This article will focus on business rules as prescribed procedures that should be followed to achieve the business's goals. The ISO 9000 documentation includes policies, procedures and instructions to assure the final product's conformance with ISO 9000 requirements. Partly for this reason, it is contended here that ISO 9000 standards and associated documents can be of a great help for business rules elicitaion. The authors' main contribution is to propose a conceptual model for not only eliciting business rules, but also integrating them into a software requirements baseline model. This proposal uses ISO 9000 characteristics and integrates them with the idea of natural language-based requirements description.


[MCC51/98]
LUCENA, C.J.P. (coord.); CRESPO, S.; LIMA, F.; FONTOURA, M.F.; PORTO, F.; COLCHER, S., (eds.) 1o. Workshop Pronex sobre Frameworks. 70 p. Port. E-mail: lucena@inf.puc-rio.br

Abstract: During the last years, Frameworks have been an important research issue in the Software Engineering area. This technology has been increasingly adopted within different research and development domains. At the PUC-Rio Computer Science Department, several research topics within specific domains have been working in order to use the framework technology as a means of increasing quality, reusability, organization and flexibility in both domain specific modeling and software construction. The Mobile Project (PRONEX) aims to  approximate the diferrent efforts stimulating cooperation among those groups. For that sake, during the year 1998, a series of seminars were held providing a forum for discussion of the work in progress. In order to finish the year's activities, the 1st. Pronex Frameworks Workshop was held on December 15o. and 21o. under the coordination of Prof. Carlos Jose Pereira de Lucena. This technical report compiles the submitted position papers. Further information can be accessed at http://www.les.inf.puc-rio.br/~pwpf.


[MCC52/98]
ARAGÃO, M.V.S.P.; PALMEIRA, M.M. Tabu serach and strong cutting planes for the flow shop scheduling problem. 8 p. Eng. E-mail: poggi@inf.puc-rio.br

Abstract: We present a Tabu Search procedure for the Flow Shop Scheduling problem (FSP) where strong cutting planes are used to implement an intensification mechanism. These cutting planes were proposed by Bellmore and Ratliff for the Set Covering problem and are strong in the sense that they also cut integer feasible solutions, but only solutions that are dominated by a known one. We show how to efficiently construct these cuts for the FSP and propose a penalty scheme to consider their violation in the resulting Tabu Search procedure. Finally, we present computational results, on benchmarks instances proposed by Taillard, which indicate that a significant improvement is obtained.


[MCC53/98]
UCHOA, E., ARAGÃO, M.V.S.P. Vertex-disjoint packing of two Steiner trees: polyhedra and branch-and-cut. 13 p. Eng. E-mail: poggi@inf.puc-rio.br

Abstract: Consider the problem of routing the electrical connections among two large terminal sets in circuit layout. A realistic model for this problem is given by the vertex-disjoint packing of two Steiner trees (2VPST), which is known to be NP-Complete. This work presents an investigation on the 2VPST polyhedra. The main idea is to depart from facet-defining inequalities for a vertex-weighted Steiner tree polyhedra. Some of the inequalities are proven to also define facets for the packing polyhedra, while others can be lifted to derive new important families of inequalities, including proven facets. Separation algorithms are also presented. The resulting branch-and-cut code has an excellent performance and is capable of solving problems on grid graphs with up 10000 vertices and 5000 terminals in a few minutes.