Data Reduction Method for Categorical Data Clustering

Categorical data clustering constitutes an important part of data mining; its relevance has recently drawn attention from several researchers. As a step in data mining, however, clustering encounters the problem of large amount of data to be processed. This article offers a solution for categorical clustering algorithms when working with high volumes of data by means of a method that summarizes the database. This is done using a structure called CM-tree. In order to test our method, the KModes and Click clustering algorithms were used with several databases. Experiments demonstrate that the proposed summarization method improves execution time, without losing clustering quality

How to find non-functional requirements in system developments

International audienceThe current complexity of systems requires a full understanding of stakeholder needs in system design. Later, these needs will become requirements of the system: functional requirements are quite easy to describe for the customer, but finding the non-functional requirements is an actual challenge; however, they are essential to design the system. The objective of this research work is to provide support when defining non-functional requirements. The proposal consists in a requirement classification and a questionnaire that progressively guides the elicitation of stakeholder needs. This method is applied to three case studies, demonstrating its interest and indicating opportunities for improvement

Avez-vous identifié toutes les parties prenantes ?

International audienceToday, there is fierce competition among companies to design and deliver products to market as soon as possible, so companies are looking to develop systems faster than ever, systems that must perfectly meet the needs of increasingly demanding customers. Researchers in systems engineering, project management, and concept definition, among other disciplines, have understood that accurately and comprehensively identifying stakeholders at the outset of a new system design project is essential to properly define needs and ultimately deliver a system that best meets diverse expectations. The objective of this article is thus to help the analysis and design teams to determine the different stakeholders of a technical system development project. Our proposal consists of a typology of stakeholders to facilitate their identification and a table to weight their contribution to the project according to their importance. The proposal, compliant with the ISO / IEC / IEEE 15288 standard (2015), has been tested in three case studies, leading to its initial validation and future opportunities for improvement.Il existe aujourd'hui une compétition féroce entre les entreprises pour concevoir et livrer des produits sur le marché dès que possible; celles-ci cherchent ainsi à développer plus rapidement que jamais des systèmes qui doivent parfaitement répondre à des besoins de clients toujours plus exigeants. Les chercheurs en ingénierie système, en gestion de projet et en définition de concept, entre autres disciplines, ont compris qu'identifier précisément et exhaustivement les parties prenantes dès le début d'un projet de conception d'un nouveau système est essentiel pour bien définir les besoins et livrer au final un système qui réponde au mieux aux diverses attentes. L'objectif de cet article est ainsi d'aider les équipes d'analyse et de conception à déterminer les différentes parties prenantes d'un projet de développement d'un système technique. Notre proposition consiste en une typologie des parties prenantes permettant de faciliter leur identification et une table pour pondérer leur contribution au projet en fonction de leur importance. La proposition, conforme à la norme ISO / IEC / IEEE 15288 (2015), a été expérimentée dans trois études de cas, aboutissant à une première validation de celle-ci et à des opportunités d'amélioration futures