Galina Medyna

Modelling, Evaluation and Simulation during the Early Design Stages: Toward the Development of an Approach Limiting the Need for Specific Knowledge

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.

Study of an exergy method for environmental evaluation assessment in the early design phase using comparative LCA and exergy approach

Environmental evaluation analysis made at an early design stage is an important practical problem because existing approaches such as the LCA method require detailed information about the studied product or service. Consequently, to be efficient such a method requires a product or service located in an advanced development phase. An exergy method offers an appropriate solution for an environmental evaluation analysis at an early design stage. The theoretical model has been validated in previous journal articles. The goal of the present article is to validate the concordance of the results provided by the exergy and LCA approach, as LCA is a widely used approach even though the scientific reliability of LCA techniques has been questioned. This paper addresses the last phase of the validation of the exergy approach by comparing results of a case study analysed through both commercial LCA software and an exergy approach.

Environmental and Economic Evaluation of Solar Thermal Panels using Exergy and Dimensional Analysis

Environmental considerations must now be taken into account more and more during the development of products and processes. As the decisions made during the early phases of development influence a large part of the final structure and cost, a quick and efficient way of evaluating environmental impact is crucial to give solid bases to the decisions. This article presents a framework for an environmental and economic evaluation that uses exergy and dimensional analysis, aimed for these early stages of design. The proposed framework is illustrated through a case study on flat solar thermal panels.

Decision Making and Value Considerations During the Early Stages of Engineering Design

Early design is a critical stage in product and service development. The choices made during this period influence the final spread and acceptance of the artifact and therefore must be made in the best possible manner. Different aspects must be taken into account during decision making such as value, risk awareness, environmental impacts, etc. The present work studies value in engineering projects using dimensional analysis and its integration in the decision making framework while putting an accent on value considerations.

Evolution of User Driven Innovation

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.© 2010 ASME

Towards an Approach for Evaluating the Quality of Requirements

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.Copyright

Evaluation of Parts of a Boat Cabin Based on Exergy: Focusing on Environmental and Economic Assessments

Product and process engineering design is a complex problem which relies on multiple fields, and while many design aid tools exist they rarely take into account more than a single field or aspect at a time. This implies that a few tools have to used for a single project, making the engineer, or designer, juggle among them or favouring a single aspect. Many existing environmental assessment tools on the market only focus on environmental aspects, which are extremely important in today’s impact conscious context but are not enough to make viable products and processes. Moreover the tools often require precise data which is only known during the late stages of design when it is too late to make any significant changes. The aim of the current work is to further develop and test a multi-domain modelling framework, for the early stages of product and process design, which primarily focuses on environmental assessment but also takes into account economic aspects and can be expanded to further fields, such as risk. The two bases for the proposed framework are exergy, a measure of useful work that can be, unlike energy, both created and destroyed, and dimensional analysis, a widely used tool in engineering to model problems through dimensional homogeneity. The environmental and economic assessments proposed by the tool are illustrated on the case of insulation of the cabin on a passenger ferry and the environmental results are compared to those from two existing methodologies, Eco-Indicator and Cumulative Exergy Demand.Copyright