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The collapse of a structure resulting from the instability of steel frames due to fire is the worst failure mode to consider in fire-structural engineering, and should be avoided. The purpose of this paper is to propose a new method for estimating the minimum possible duration of a fire event that could result in the instability of an unbraced steel frame.

The proposed method is in the form of a constrained minimization problem that determines the worst case fire scenario that can cause instability of a structure, and is solved using nonlinear constrained mathematical programming algorithms. The formulation is demonstrated via a numerical example.

For frames subjected to fire events modelled with monotonically increasing fire curves, the worst case fire causing instability of a frame is always one where all of the compartments catch fire at the same time. For frames subjected to fire events where fire curves decay, the minimization problem must be solved rigorously. The results are significantly affected by the fire curves and amount of insulation applied to each member.

The proposed method is an extension of a method previously established by Xu et al. (2018) to assess the stability of unbraced steel frames subjected to elevated member temperatures. The previous method does not consider fire duration and heat transfer mechanics, which are included in the proposed method. The proposed method is potentially useful for designers in conducting fire scenario analysis in the performance-based design of structures.

The present paper addresses the computer modelling of pipe formation in metal castings.

As a preliminary, a brief review of the current state‐of‐the‐art in pipe shrinkage computation is presented. Then, in first part, the constitutive equations that have to be considered in thermomechanical computations are presented, followed by the main lines of the mechanical finite element resolution. A detailed presentation of an original arbitrary Lagrangian‐Eulerian (ALE) formulation is given, explaining the connection between the Lagrangian and the quasi Eulerian zones, and the treatment of free surfaces.

Whereas most existing methods are based on thermal considerations only, it is demonstrated in the current paper that this typical evolution of the free surface, originated by shrinkage at solidification front and compensating feeding liquid flow, can be effectively approached by a thermomechanical finite element analysis.

Future work should deal with the following points: identification of thermo‐physical and rheological data, automatic and adaptive mesh refinement, calculation of the coupled deformation of mold components, development of a two‐phase solid/liquid formulation.

An example of industrial application is given. The proposed method has been implemented in the commercial software THERCAST^® dedicated to casting simulation.

The proposed numerical methods provide a comprehensive approach, capable of modelling concurrently all the main phenomena participating in pipe formation.

Recent efforts to formulate strategies that will turn Qatar's capital city into a global hub have given rise to a debate about the morphological and functional composition of one of Doha's most prominent areas - West Bay. At the end of the 20th century West Bay, also known as Diplomatic Quarter, was chosen by public initiatives to become the new Central Business District of Doha. Today, the appeal of West Bay as a business hub is contested by other emerging urban centres – such as the highly integrated Al Sadd area, which has attracted a wide range of advanced producer service sectors. It is therefore the objective of this paper to investigate the spatial configuration of Doha's West Bay, which arguably lays the foundations for the socio-economic interdependencies necessary for its vitality and sustenance. In order to quantify its intrinsic urban complexities, Bill Hillier's space syntax methodology is applied, which elucidates, in various scales, global and local grid conditions, and thus can be used for assessments regarding the distribution of land use patterns and infrastructural networks.

THE army of young unemployed is a blot on our civilisation. That much would be agreed by all. That nothing very positive is being done about it is also all too evident.

In order to optimize production and save material, numerical simulation is becoming more and more used in industrial forging processes.

From the tourist point of view the chief purpose of travel is that the destination should be different from home and better in some ways. In Jamaica, the environment, both natural and man‐made, remains the backbone of the tourism product. The maintenance and protection of the environment is therefore crucial to the continuing growth of the island's tourist industry.

This paper aims to develop a robust set of advanced numerical tools to simulate multiphase flows under the superimposition of external uniform magnetic fields.

The flow has been simulated in a fully Eulerian framework by a {\it variational multi-scale} method, which allows to take into account the small-scale turbulence without explicitly model it. The multi-fluid problem has been solved through the convectively re-initialized level-set method to robustly deal with high density and viscosity ratio between the phases and the surface tension has been modelled implicitly in the level-set framework. The interaction with the magnetic field has been modelled through the classic induction equation for 2D problems and the time step computation is based on the electromagnetic interaction to guarantee convergence of the method. Anisotropic mesh adaptation is then used to adapt the mesh to the main problem’s variables and to reach good accuracy with a small number of degrees of freedom. Finally, the variational multiscale method leads to a natural stabilization of the finite elements algorithm, preventing numerical spurious oscillations in the solution of Navier–Stokes equations (fluid mechanics) and the transport equation (level-set convection).

The methodology has been validated, and it is shown to produce accurate results also with a low number of degrees of freedom. The physical effect of the external magnetic field on the multiphase flow has been analysed.

The dam-break benchmark case has been extended to include magnetically constrained flows.

The purpose of this paper is to study the influence of the induction heating phenomenon during magnetic pulse forming (MPF) of thin walled tube components. The approach is based on the advanced use of the multiphysics finite element software FORGE® coupling electromagnetism, heat transfer and solid mechanics. Although the global contribution of thermal effects is found to be almost negligible with respect to the volume forces, it can be observed that localized softening due to the heating process induces shock absorbing behavior.

Due to the strong multiphysics couplings between solid mechanics, electromagnetism and heat transfer, it is not always obvious to quantify the contributions of the various physical phenomena. It is thus intended here to take advantage of the numerical framework and tool that has developed to dissociate and quantify the influence of Joule heating phenomena due to eddy currents during MPF processes.

In this paper, the sensitivity of the MPF process has been analyzed to the induction heating source term for a specific tube forming case. An analysis of the electric output signal shows that inductance sensitivity to heating remains small when compared to the mechanical deformation. Regarding mechanical analysis of the process, induction heating contribution has a very slight impact at the global scale, but its effect is more noticeable at the small scale where it is likely that the localized heating induces shock absorption properties through softening. The extension of these results to other materials (for which the thermal dependency of mechanical behavior is different), as well as to a larger range of energy inputs, still needs to be carried out. Such phenomena should be considered for instance for high precision forming.

The analysis of the influence of heating due to eddy currents in magnetic pulse forming processes has not been extensively studied. The originality of this work is to try to quantify its effect on the process by using a numerical-based approach.

This study intends to explore the opportunities and roles of Macao's universities in the education and training development of Hengqin under the General Plan of the Development of the Guangdong–Macao In-Depth Cooperation Zone in Hengqin promulgated in August 2021.

This study is intended to analyze the role of Macao’ universities in Hengqin development, based on data collected through interviewing with dozens of scholars and government officials from Macao and Hengqin, and government reports, news reports and other relevant data.

The General Plan provides Macao's universities with opportunities to develop education and training in Hengqin. On the one hand, Hengqin can be the locus of Macao's tertiary education diversification; Macao's universities can jointly establish technological research institutions and set up postdoctoral research centers and university branches to enroll master's and doctoral students from Mainland China. On the other hand, Macao's universities can set up a branch of professional training and open training courses in Hengqin. These efforts are designed to promote technological innovation and cultural diffusion in Macao.

This study analyses the potential role of Macao's universities in developing education and training in Hengqin since the central policy was announced last August. This study will be of interest to scholars as well as policymakers.