Genny Tortora

Enhancing an artefact management system with traceability recovery features

We present a traceability recovery method and tool based on latent semantic indexing (LSI) in the context of an artefact management system. The tool highlights the candidate links not identified yet by the software engineer and the links identified but missed by the tool, probably due to inconsistencies in the usage of domain terms in the traced software artefacts. We also present a case study of using the traceability recovery tool on software artefacts belonging to different categories of documents, including requirement, design, and testing documents, as well as code components.

ADAMS Re-Trace: a traceability recovery tool

We present the traceability recovery tool developed in the ADAMS artefact management system. The tool is based on an information retrieval technique, namely latent semantic indexing and aims at supporting the software engineer in the identification of the traceability links between artefacts of different types. We also present a case study involving seven student projects, which represented an ideal workbench for the tool. The results emphasise the benefits provided by the tool in terms of new traceability links discovered, in addition to the links manually traced by the software engineer. Moreover, the tool was also helpful in identifying cases of lack of similarity between artefacts manually traced by the software engineer, thus revealing inconsistencies in the usage of domain terms in these artefacts. This information is valuable to assess the quality of the produced artefacts.

NABS: Novel Approaches for Biometric Systems

Research on biometrics has noticeably increased. However, no single bodily or behavioral feature is able to satisfy acceptability, speed, and reliability constraints of authentication in real applications. The present trend is therefore toward multimodal systems. In this paper, we deal with some core issues related to the design of these systems and propose a novel modular framework, namely, novel approaches for biometric systems (NABS) that we have implemented to address them. NABS proposal encompasses two possible architectures based on the comparative speeds of the involved biometries. It also provides a novel solution for the data normalization problem, with the new quasi-linear sigmoid (QLS) normalization function. This function can overcome a number of common limitations, according to the presented experimental comparisons. A further contribution is the system response reliability (SRR) index to measure response confidence. Its theoretical definition allows to take into account the gallery composition at hand in assigning a system reliability measure on a single-response basis. The unified experimental setting aims at evaluating such aspects both separately and together, using face, ear, and fingerprint as test biometries. The results provide a positive feedback for the overall theoretical framework developed herein. Since NABS is designed to allow both a flexible choice of the adopted architecture, and a variable compositions and/or substitution of its optional modules, i.e., QLS and SRR, it can support different operational settings.

Reengineering Web applications based on cloned pattern analysis

Web applications are subject to continuous and rapid evolution. Often it happens that programmers indiscriminately duplicate Web pages without considering systematic development and maintenance methods. This practice creates code clones that make Web applications hard to maintain and reuse. This paper presents an approach for reengineering Web applications based on clone analysis that aims at identifying and generalizing static and dynamic pages and navigational patterns of a Web application. Clone analysis is also helpful for identifying literals that can be generated from a database. A case study is described which shows how the proposed approach can be used for restructuring the navigational structure of a Web application by removing redundant code.

Data Model Comprehension: An Empirical Comparison of ER and UML Class Diagrams

We present the results of two controlled experiments to compare ER and UML class diagrams, in order to find out which of the models provides better support during the comprehension of data models. The experiment involved Master and Bachelor students performing comprehension tasks on data models represented by ER or UML class diagrams. The achieved results show that UML class diagrams significantly improve the comprehension level achieved by subjects. Moreover, having different subjects with different levels of ability and experience allowed us to also make some considerations on the influence of such factors on the comprehension performances.

Understanding cloned patterns in Web applications

We propose a tool to identify and analyze cloned patterns in Web applications using clone analysis and clustering of static and dynamic Web pages. The tool first detects cloned pages, which are then grouped into clusters as well as the groups of links between clusters. In this way the navigational schema is simplified and the duplicated functionalities corresponding to cloned navigational patterns can be more easily analyzed. The tool also allows filtering out uninteresting parts of the restructured navigational schema, thus to further improve the understanding.

IME: an image management environment with content-based access

Abstract The article describes an experimental visual environment to handle digital images by contents. A suitable spatial index is used to organize the images in a spatial access structure for efficient storage and retrieval. An image is indexed according to both the spatial arrangement of its objects and the morphological and geometrical measures of these objects. Therefore, in the database population phase a user identifies the objects that characterize the visual content of each image by a user-friendly interface. In order to let the system retrieve images based on the presence of given patterns, it is necessary to define similarity matching criteria between a query and an image. To efficiently perform such a match, each image is stored together with a collection of metadata that are a very compact representation of the visual contents of the image. These metadata form the index of the image. The system implements a Spatial Access Method based on k-d-trees to achieve a significant speedup over sequential search. We prove the effectiveness and the efficiency of the system by performing standard tests on a database containing a large number of medical images, namely lung CT scans.

Visual-language system for user interfaces

The Universities of Pittsburgh and Salerno have jointly developed the Pittsburgh-Salerno Iconic System which lets users design, specify, and interpret custom visual languages for different applications. The system is still in the experimental stage, although we have used it in two practical applications. The experimental system lets interface developers create a custom visual language from sample visual sentences composed of custom or basic icons. The system has already been tested in two small applications, one involving a system for speech-impaired users. >

Enhancing collaborative synchronous UML modelling with fine-grained versioning of software artefacts

Software development teams are composed of people with different knowledge and skills, who contribute to a project from often widely dispersed locations. Software development in geographically distributed environments creates software engineering challenges due to the interaction among members of distributed teams and the management of consistency and concurrency among project artefacts. In this paper, we propose Synchronous collaborative modelling Tool Enhanced with VErsioning management (STEVE) a collaborative tool supporting distributed Unified Modelling Language (UML) modelling of software systems. The tool provides a communication infrastructure enabling the concurrent editing of the same UML diagram at the same time by distributed developers. Complex UML diagrams are decomposed and managed in a fine-grained hierarchy of sub-artefacts, thus providing change and configuration management functionalities for both the diagram and the graphical objects. Thus, software predefined diagram components can be consistently reused and shared across different diagrams of a given project.

Investigative analysis across documents and drawings: visual analytics for archaeologists

With the invention and rapid improvement of data-capturing devices, such as satellite imagery and digital cameras, the information that archaeologists must manage in their everydays activities has rapidly grown in complexity and amount. In this work we present Indiana Finder, an interactive visualization system that supports archaeologists in the examination of large repositories of documents and drawings. In particular, the system provides visual analytic support for investigative analysis such as the interpretation of new archaeological findings, the detection of interpretation anomalies, and the discovery of new insights. We illustrate the potential of Indiana Finder in the context of the digital protection and conservation of rock art natural and cultural heritage sites. In this domain, Indiana Finder provides an integrated environment that archaeologists can exploit to investigate, discover, and learn from textual documents, pictures, and drawings related to rock carvings. This goal is accomplished through novel visualization methods including visual similarity ring charts that may help archaeologists in the hard task of dating a symbol in a rock engraving based on its shape and on the surrounding symbols.