Editorial

Citation

Khalil, I. (2009), "Editorial", International Journal of Web Information Systems, Vol. 5 No. 3. https://doi.org/10.1108/ijwis.2009.36205caa.001

Editorial

Article Type: Editorial From: International Journal of Web Information Systems, Volume 5, Issue 3

With this issue, International Journal of Web Information Systems (IJWIS) is proving to be a leading international journal for researchers and industry practitioners to share their new ideas, original research results and practical development experiences from all web information systems related areas. This issue consists of five papers addresses issues, research, and development projects and methodologies for web information systems. The first paper “A survey on model versioning approaches” by Kerstin Altmanninger, Martina Seidl, and Manuel Wimmer from Austria provides a thorough insight into the feature-based characterization of version control systems focusing on collaboration support, current model versioning approaches, and according challenges.

The second paper “Efficient XML tree pattern query evaluation using a novel one-phase holistic twig join scheme” by Zhewei Jiang, Cheng Luo, Wen-Chi Hou, Dunren Che, and Qiang Zhu from the USA aims to provide an efficient algorithm for XML twig query evaluation. The paper proposes a single-phase holistic twig pattern matching method based on the TwigStack algorithm. The method applies a novel stack structure to preserve the holisticity of the twig matches. Twig matches rooted at elements that are currently in the root stack are output directly. Without generating individual path matches as intermediate results, the method is able to avoid the storage and output/input of the individual path matches, and totally eliminate the potentially time-consuming merging operation. Experimental results demonstrate the applicability and advantages of the approach.

The third paper “An efficient mapping schema for storing and accessing XML data in relational databases” by Jun Wu and Shang-Yi Huang from Taiwan, ROC proposes a new approach to eliminate the join operations for parent-child traversing and/or sibling searching such that the performance of query processing could be improved. The rationale behind the design of the proposed approach is to distribute the structural information into relational databases. The paper finds that the number of join operations which are needed for processing parent-child traversal and sibling search can be bounded under the proposed approach.

The fourth paper “A new approach to web users clustering and validation: a divergence-based scheme” by Vassiliki A. Koutsonikola, Sophia G. Petridou, Athena I. Vakali, and Georgios I. Papadimitriou from Greece examines the usage of Kullback-Leibler divergence (KL-divergence), an information theoretic distance, as an alternative option for measuring distances in web users clustering. KL-divergence is compared with other well-known distance measures and clustering results are evaluated using a criterion function, validity indices and graphical representations. Furthermore, the impact of noise (i.e. occasional or mistaken page visits) is evaluated, since it is imperative to assess whether a clustering process exhibits tolerance in noisy environments such as the web.

The proposed KL clustering approach is of similar performance when compared with other distance measures under both synthetic and real data workloads. Moreover, imposing extra noise on real data our approach shows minimum deterioration among most of the other conventional distance measures.

The last paper in this issue “A semi-automatic approach for bridging DSMLs with UML” by Manuel Wimmer from Austria focuses on integrating direction domain-specific modeling languages (DSMLs) with unified modeling language (UML). Although, DSMLs defined as metamodels and UML profiles are frequently applied in practice, only few attempts have been made to provide interoperability between these two worlds. The contribution of this paper is to integrate the so far competing worlds of DSMLs and UML by proposing a semi-automatic approach, which allows exchanging models between these two worlds without loss of information.

With this issue of IJWIS, we would like to thank the authors, referees, and the editorial board for their efforts and contributions to this issue.

Ismail Khalil