The early stages of the design process are keys in the development of products and services. Nevertheless, they are marked by multiple constraints imposed on them, such as, most notably, a limited amount of time available for modelling and evaluating ideas and concepts. The present article develops an approach for modelling, and simulating initial design solutions during these critical early stages. The final objective is to minimize the amount of prerequisite knowledge a designer should have on the artefact being designed in order to propose, develop, and evaluate early models. First, the current work analyses the conditions necessary to develop a modelling and comparison environment for early design solutions. This is done through mathematical considerations of the design process. In a second part, the work proposes a modelling and simulation approach and develops the machinery behind it. The approach integrates and maps a series of normalized semantic descriptions of functions, generic engineering components and variables, a set of elementary laws associated with these components, and a set of elementary base units. All these elements are used to refine and guide the modelling process. This process is uses the Vaschy-Buckingham theorem followed by an approximation of the generic law describing the general behaviour of elementary components. This combination leads to an approximated model of the behaviour of the studied artefact. The model is further developed by implementing the behaviour in a system dynamics tool using two basic bricks of the system dynamics language, converters and flows. In a final part, the approach is illustrated through the case study of a beam structure.

article accessible aussi en ligne via le lien suivant : www.cairn.info/revue-journal-of-innovation-economics-2014-3-page-59.htm.International audienceThe "hierarchical and linear model of innovation" (HLMI) is often used to describe how innovations are produced. HLMI presents several shortcomings and one possible way of overcoming them is to consider innovations from a system perspective. In order to achieve this, this article uses Kline and Rosenberg's chain-linked model (CLM, 1985) as a starting point and builds up on it, proposing an improvement rendering CLM more coherent with its systemic bases. The proposed improvement suggests conceiving innovation systems as associations of building blocks and using contemporary engineering diagram-based languages to display them. Nevertheless, this improvement does not challenge the dynamic features of innovation system

The source and driver of user driven innovation is a profound understanding of customer needs. Three main approaches to user driven innovation exist: a traditional sequential approach, a lead user approach and customer co-creation. The overall trend is toward increasing user participation throughout the innovation process. Today the leading companies successfully engage users into creative processes of their innovation activities starting in the early stages. In the energy sector user driven innovation methodologies appear promising, in particular as a mean to improve energy efficiency and save energy. This paper focuses on the evolution of user driven innovation. We present an ontology of user driven innovation. It is followed by a state-of-the-art analysis of traditional and new approaches. Finally we try to predict whether a user driven innovation approach could aid the energy sector in overcoming challenges related to global warming and oil shortage.

In engineering design, the needs of stakeholders are often captured and expressed in natural language (NL). While this facilitates such tasks as sharing information with non-specialists, there are several associated problems including ambiguity, incompleteness, understandability, and testability. Traditionally, these issues were managed through tedious procedures such as reading requirements documents and looking for errors, but new approaches are being developed to assist designers in collecting, analysing, and clarifying requirements. The quality of the end-product is strongly related to the clarity of requirements and, thus, requirements should be managed carefully. This paper proposes to combine diverse requirements quality measures found from literature. These metrics are coherently integrated in a single software tool. This paper also proposes a new metric for clustering requirements based on their similarity to increase the quality of requirement model. The proposed methodology is tested on a case study and results show that this tool provides designers with insight on the quality of individual requirements as well as with a holistic assessment of the entire set of requirements.

An important goal across Sub-Saharan Africa (SSA), and globally, is to foster a healthy nutrition. A strengthening of the diversity, sustainability, resilience and connectivity of food systems is increasingly seen as a key leverage point. Governance arrangements play a central role in connecting sustainable, resilient farming with healthy nutrition. In this article, we elaborate a framework for assessing, monitoring and improving the governance of food systems. Our focus is on food chains in six peri-urban and urban regions in SSA. A literature review on food chain governance and a mapping of current agri-food chains in the six regions provide the basis for the elaboration of an indicator-based assessment framework. The framework is adapted to the specific conditions of SSA and related goals. The assessment framework is then used to identify the challenges and opportunities in food chain governance in the six regions. The first testing of the framework indicates that the approach can help to identify disconnects, conflicting goals and tensions in food systems, and to formulate strategies for empowering agri-food chain actors in transitioning toward more efficient, equitable and sustainable agri-food systems. The article is concluded with a brief reflection on the strengths and weaknesses of the framework and suggests further testing and refinement.