Done well, separation of concerns can provide many software engineering benefits, including reduced complexity, improved reusability, and simpler evolution. The choice of boundaries for separate concerns depends on both requirements on the system and on the kind(s) of decompositionand composition a

5 (MEGA5), which is a user-friendly software for mining online databases, building sequence alignments and phylogenetic trees, and using methods of evolutionary bioinformatics in basic biology, biomedicine, and evolution. The newest addition in MEGA5 is a collection of maximum likelihood (ML

PAML, currently in version 4, is a package of programs for phylogenetic analyses of DNA and protein sequences using maximum likelihood (ML). The programs may be used to compare and test phylogenetic trees, but their main strengths lie in the rich repertoire of evolutionary models implemented, which

Continuous availability is a critical requirement for an important class of software systems. For these systems, runtime system evolution can mitigate the costs and risks associated with shutting down and restarting the system for an update. We present an architecture-based approach to runtime

that the system accommodate such change dynamically, without stopping or disturbing the operation of those parts of the system unaffected by the change. Since the description of software structure (components and interconnections) provides a clear means for both sys-tem comprehension and construction, it seems

Most studies of software evolution have been performed on systems developed within a single company using traditional management techniques. With the widespread availability of several large software systems that have been developed using an “open source ” development approach, we now have a chance

, we determine a dendrogram (ternary tree) by a new quartet method and a fast heuristic to implement it. The method is implemented and available as public software, and is robust under choice of different compressors. To substantiate our claims of universality and robustness, we report evidence

, and inhibiting software evolution. ArchJava is an extension to Java that seamlessly unifies software architecture with implementation, ensuring that the implementation conforms to architectural constraints. A case study applying ArchJava to a circuit-design application suggests that ArchJava can express

or analysis of other literature. This paper, in contrast, follows an empirical approach. Focus groups and interviews conducted in 26 major software development organizations demonstrate a wide range of traceability practices with distinct low-end and high-end users of traceability. From these observations

This paper discusses the use of genetic algorithms (GAs) for automatic software test data generation. This research extends previous work on dynamic test data generation where the problem of test data generation is reduced to one of minimizing a function [Miller and Spooner, 1976, Korel, 1990