Abstract in English:

Agile Methods propose a new way of looking at software development that questions many of the beliefs of conventional Software Engineering. Agile methods such as Extreme Programming (XP) have been very effective in producing highquality software in realworld projects with strict time constraints. Nevertheless, most university courses and industrial training programs are still based on oldstyle heavy-weight methods. This article, based on our experiences teaching XP in academic and industrial environments, presents effective ways of teaching students and professionals on how to develop high-quality software following the principles of agile software development. We also discuss related work in the area, describe realworld cases, and discuss open problems not yet resolved.

Abstract in English:

Agile software processes emerged to address the issue of building software on time and within the planned budget. To adopt an agile process, it is imperative to analyze and evaluate its effectiveness in supporting high quality software development while complying with stringent time constraints. In this paper we describe an agile method for Web-based application development (XWebProcess) and an experiment conducted with a group of forty senior undergraduate students to assess the quality/speed effectiveness of the proposed method vis-à-vis the effectiveness of Extreme Programming (XP). The results have shown that the process proposed is equally agile when compared to XP, moreover, surveys conducted as part of the experiment pointed out that XWebProcess is more suitable to Web development in dimensions such as requirements gathering, user interface and navigation design, and software testing, therefore leading to better quality software.

Abstract in English:

Design patterns offer flexible solutions to common problems in software development. Recent studies have shown that several design patterns involve crosscutting concerns. Unfortunately, object-oriented (OO) abstractions are often not able to modularize those crosscutting concerns, which in turn decrease the system reusability and maintainability. Hence, it is important verifying whether aspect-oriented approaches support improved modularization of crosscutting concerns relative to design patterns. Ideally, quantitative studies should be performed to compare object-oriented and aspect-oriented implementations of classical patterns with respect to important software engineering attributes, such as coupling and cohesion. This paper presents a quantitative study that compares aspect-based and OO solutions for a representative set of design patterns. We have used stringent software engineering attributes as the assessment criteria. We have found that most aspect-oriented solutions improve separation of pattern-related concerns, although some aspect-oriented implementations of specific patterns resulted in higher coupling and more lines of code.

Abstract in English:

This paper presents the application of a formal testing methodology to protocols and services for wireless telephony networks. The methodology provides a complete and integrated coverage of all phases of the testing procedure: specification, test generation, and test execution on a given architecture. It permits to perform conformance and interoperability testing detecting different kinds of implementation faults, as for instance output and transmission faults. The test execution is performed in the framework of a set of architectures capable to deal with different environments. Telecommunication systems and mobility are the main focus of the application presented in this paper. Two case studies illustrates the application of the methodology to a wireless telephone network: conformance and interoperability testing of Wireless Application Protocol (WAP) protocols and services based on the subscriber location.

Abstract in English:

Distributed Shared Memory systems allow the use of the shared memory programming paradigm in distributed architectures where no physically shared memory exist. Scope consistent software DSMs provide a relaxed memory model that reduces the coherence overhead by ensuring consistency only at synchronization operations, on a per-lock basis. Much of the work in DSM systems is validated by benchmarks and there are only a few examples of real parallel applications running on DSM systems. Sequence comparison is a basic operation in DNA sequencing projects, and most of sequence comparison methods used are based on heuristics, that are faster but do not produce optimal alignments. Recently, many organisms had their DNA entirely sequenced, and this reality presents the need for comparing long DNA sequences, which is a challenging task due to its high demands for computational power and memory. In this article, we present and evaluate a parallelization strategy for implementing a sequence alignment algorithm for long sequences. This strategy was implemented in JIAJIA, a scope consistent software DSM system. Our results on an eight-machine cluster presented good speedups, showing that our parallelization strategy and programming support were appropriate.