High-Accuracy X-Ray Diffraction Analysis of Phase Evolution Sequence During Devitrification of Cu50Zr50 Metallic Glass

Real-time high-energy X-ray diffraction (HEXRD) was used to investigate the crystallization kinetics and phase selection sequence for constant-heating-rate devitrification of fully amorphous Cu50Zr50, using heating rates from 10 K/min to 60 K/min (10 °C/min to 60 °C/min). In situ HEXRD patterns were obtained by the constant-rate heating of melt-spun ribbons under synchrotron radiation. High-accuracy phase identification and quantitative assessment of phase fraction evolution though the duration of the observed transformations were performed using a Rietveld refinement method. Results for 10 K/min (10 °C/min) heating show the apparent simultaneous formation of three phases, orthorhombic Cu10Zr7, tetragonal CuZr2 (C11b), and cubic CuZr (B2), at 706 K (433 °C), followed immediately by the dissolution of the CuZr (B2) phase upon continued heating to 789 K (516 °C). Continued heating results in reprecipitation of the CuZr (B2) phase at 1002 K (729 °C), with the material transforming completely to CuZr (B2) by 1045 K (772 °C). The Cu5Zr8 phase, previously reported to be a devitrification product in C50Zr50, was not observed in the present study

An Event-Based Model to simulate human behaviour in built environments

During a design process, few methods allow designers to evaluate if and how the future building will match and affect its intended use and its intended users. Computer simulation techniques have focused on prediction of human behavior in built environments in order to overcome this lack; nevertheless, their applications are limited to representation of specifi c behavioral aspects while a reliable representation of building response to actual use is still missing. Based on current developments in the video game industry, the research described here aims to establish a new approach to simulating human behavior in buildings, centered on a clear definition of use scenarios as specific structures of active entities called Events. They provide information about occurrences happening during the use process in terms of Actors involved, Activities performed and Space where the event takes place. Equipped with AI engines, events control and coordinate the actorsí behavior during the simulation, representing their interaction, cooperation and collaboration

Using Game-Like Narrative to Simulate Human Behaviour in Built Environments

Predicting future users’ behaviour and their activities in a building is a highly complex task that designers have to face during the design process. Despite its importance, few methods exist that can predict and help evaluate this type of building performance during the design process itself. Simulative approaches are gradually overcoming this shortcoming, but at present their application is limited to the representation of specific occurrences and behavioural performance aspects, such as emergency egress. Based on current developments in the video game industry, our research aims to establish a new approach to human behaviour simulation in built environments, based on a clear and reliable representation of the use processes occurring in a building. At its core is simulation based on the notion of events, defined as active entities on their own, comprised of space, people, and activities. These events entities are structured into collections called narratives, which represent and allow the simulation of the step-by-step performing of activities by users in a built environment

BIM and simulation of building use processes

Since its advent, Building Information Modelling approach has been gradually extended from the sole representation of the Building and of its components (BIM 3D) to the management of knowledge related to construction time (BIM 4D), costs estimation (BIM 5D) and building life cycle (BIM 6D). Nevertheless, a relevant factor as the building functional response to the activities of its intended users is still underrepresented by current BIM and IFC models. As result, designers are still forced to make decisions that will impact the building future use just relying on norms, regulations and manuals, or on their previous professional experience. The consequences are often clear in our world: after their construction, many buildings don’t work as expected, but it is usually too late or too costly to intervene. The research described in this paper aims at: 1) extending the current BIM approach in order to include semantics related to the building use process; 2) integrate this model with a virtual simulation environment, where the designers can observe how the building will interact with its intended users. The proposed model is based on an ontology-based representation of the building use process, structured in terms of activities performed, users involved and building spaces where they are located. This static representation is associated to a simulation engine derived from the videogames industry, where the use process previously formalized is simulated and dynamically visualized. This system allows designers and clients to predict and evaluate how the building will be used and experienced before it will be actually realized and occupied, when it is still possible to in-crease the quality of the final product and solve errors and problems.To test and calibrate the model, some experiments have been developed in the hospital design field, simulating the functioning of some hospital wards both under routine and emergency scenarios

Adding users' dimension to BIM

In the last few years, several researches have added new dimensions to the usual 3D BIM approach, progressively including information about construction time (BIM 4D), costs estimation (BIM 5D) and life-cycle management (BIM 6D). Nevertheless, a key factor such as the building’s interaction with its intended use and users is still under-represented by current BIM and IFC models: many users-related decisions are based on a set of average users requirements and on the assumption that, in this way, the future building will fulfil the needs of the majority of users. In this paper, we propose to include use’ and users’ semantics in current BIM representation, and to integrate it with the virtual simulation of the building use phenomenon. Its main objective is to provide a visualization of how the future building will actually be used and experienced, before stepping into its construction. This allows designers to test and evaluate the impact of their decisions on future users’ life and activities in the proposed built environment during the design phases, when it is still possible to intervene and improve the quality of the final product by solving critical issues and reducing time and costs

Collaborative Working Environments for Architectural Design.

Prefazione: inquadramento storico della progettazione collaborativa nell'ambito della progettazione assistita. Introduzione: illustrazione delle caratteristiche di tale paradigma in vari ambiti attraverso saggi che ne evidenziano le necessità e le potenzialità. Conclusione: prospettive della progettazione collaborativa.Preface: historical framework of collaborative design in the field of computer aided design. Introduction: illustration of the characteristics of this paradigm in various fields through essays that highlight the need and potential. Conclusion: prospects for collaborative design