Modèle entité-association

Résumé

vignette|Un artiste peut jouer une chanson.|258x258px Le modèle entité-association (MEA) (le terme « modèle-entité-relation » est une traduction erronée largement répandue), ou diagramme entité-association ou en anglais « entity-relationship diagram », abrégé en ERD, est un modèle de données ou diagramme pour des descriptions de haut niveau de modèles conceptuels de données. Il a été conçu par Peter Chen dans les années 1970 afin de fournir une notation unifiée pour représenter les informations gérées par les systèmes de gestion de bases de données de l'époque. Il fournit une description graphique pour représenter des modèles de données sous la forme de diagrammes contenant des entités et des associations. De tels modèles sont utilisés dans les phases amont de conception des systèmes informatiques. Ils sont utilisés, par exemple, pour décrire les besoins en information et/ou le type d'information qui doit être enregistré dans les bases de données pendant la phase d'élaboration du ca

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https://fr.wikipedia.org/wiki/Mod%C3%A8le_entit%C3%A9-association

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Composite Relationship Fields with Transformers for Scene Graph Generation

George Adaimi, Alexandre Massoud Alahi, David Mizrahi

Scene graph generation (SGG) methods extract relationships between objects. While most methods focus on improving top-down approaches, which build a scene graph based on detected objects from an off-the-shelf object detector, there is a limited amount of work on bottom-up approaches, which jointly detect objects and their relationships in a single stage. In this work, we present a novel bottom-up SGG approach by representing relationships using Composite Relationship Fields (CoRF). CoRF turns relationship detection into a dense regression and classification task, where each cell of the output feature map identifies surrounding objects and their relationships. Furthermore, we propose a refinement head that leverages Transformers for global scene reasoning, resulting in more meaningful relationship predictions. By combining both contributions, our method outperforms previous bottom-up methods on the Visual Genome dataset by 26% while preserving real-time performance.

2023

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An object-oriented approach to manage the multiple representations of real entities

EPFL1996

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Product relationships management enabler for concurrent engineering and product lifecycle management

The current competitive industrial context requires more flexible, intelligent and compact product lifecycles, especially in the product development process where several lifecycle issues have to be considered, so as to deliver lifecycle oriented products. This paper describes the application of a novel product relationships management approach, in the context of product lifecycle management (PLM), enabling concurrent product design and assembly sequence planning. Previous work has provided a foundation through a theoretical framework, enhanced by the paradigm of product relational design and management. This statement therefore highlights the concurrent and proactive aspect of assembly oriented design vision. Central to this approach is the establishment and implementation of a complex and multiple viewpoints of product development addressing various stakeholders design and assembly planning points of view. By establishing such comprehensive relationships and identifying related relationships among several lifecycle phases, it is then possible to undertake the product design and assembly phases concurrently. Specifically, the proposed work and its application enable the management of product relationship information at the interface of product-process data management techniques. Based on the theory, models and techniques such as described in previous work, the implementation of a new hub application called PEGASUS is then described. Also based on web service technology, PEGASUS can be considered as a mediator application and/or an enabler for PLM that externalises product relationships and enables the control of information flow with internal regulation procedures. The feasibility of the approach is justified and the associated benefits are reported with a mechanical assembly as a case study. (C) 2013 Elsevier B.V. All rights reserved.

Elsevier2013

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