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Material-based computation has been recently introduced in architectural education, where parameters and rules related to materials are integrated into algorithmic thinking. The authors aim to identify affordances of material-based computation in terms of supporting the understanding of parametric design, informing the process of parametric form finding in an educational setup and augmenting student learning outcomes.

The authors propose a material-informed holistic systems design framework for parametric form finding. The authors develop a pedagogical approach that employs material-based computation focusing on the interplay between the physical and the digital in a parametrically driven façade design exercise. The approach comprises two phases: (1) enabling physical exploration with different materials to arrive at the design logic of a panel prototype and (2) deducing embedded and controlled parameters, based on the interplay of materials and deriving strategies for pattern propagation of the panel on a façade composition using variation and complexity.

The results confirmed the initial hypothesis, where the more explicit the material exploration and identification of physical rules and relations, the more nuanced the parametrically driven process, where students expressed a clear goal oriented generative logic and utilized parametric design to inform form finding as a bottom-up approach.

Most precedent approaches developed to teach parametric design concepts in architectural education have focused on universal strategies that often result in fixating students on following standard blindly followed scripts and procedures, thus defying the purpose of a bottom-up form finding framework. The approach expands the pedagogical strategies employed to address parametric design as a form finding process.

The aim of this article is to obtain a stable tensegrity structure by using the minimum knowledge of the structure.

Three methods have been formulated based on the eigen value decomposition (EVD) and singular value decomposition theorems. These two theorems are being implemented on the matrices, which are computed from the minimal data of the structure. The required minimum data for the structure is the dimension of the structure, the connectivity matrix of the structure and the initial force density matrix computed from the type of elements. The stability of the structure is analyzed based on the rank deficiency of the force density matrix and equilibrium matrix.

The main purpose of this article is to use the defined methods to find (1) the nodal coordinates of the structure, (2) the final force density values of the structure, (3) single self-stress from multiple self-stresses and (4) the stable structure.

By using the defined approaches, one can understand the difference of each method, which includes, (1) the selection of eigenvalues, (2) the selection of nodal coordinates from the first decomposition theorem, (3) the selection of mechanism mode and force density values further and (4) the solution of single feasible self-stress from multiple self-stresses.

The purpose of this paper is to build a new deployable antenna with folded scissors ribs and to evaluate the reasonable characteristics of this new structure.

Based on the TerrStar-1 satellite, virtual design and shapes forming are considered in this paper with the structure design of the new antenna. Considering the relaxation units in net surface, form-finding evaluation is used to build mathematical model and operate the optimization algorithm so that the design of the new antenna with folded scissors ribs is achieved. Simulations are carried out to verify the antenna proposed.

It is found that the antenna with folded scissors ribs can be developed smoothly in the space.

The proposed the antenna with folded scissors ribs can be considered as a fall-back alternative for large antenna, with a diameter of over 10 m in the space, or is seen as another option for the system with a simple rigid structure.

Different from traditional antenna, it provides a valuable reference for the further research of large deployable antenna in space. The antenna in this paper is able to develop more than 30 m of diameter. Meanwhile, the surface density and the natural frequency and the root-mean-square error in surface are superior to those of the traditional antenna.

The determination of feasible self-stress modes and grouping of elements for tensegrities with predefined geometry and multiple self-stress modes is very important, though difficult, in the design of these structures. The purpose of this paper is to present a novel approach to the automated element grouping and self-stress identification of tensegrities.

A set of feasible solutions conforming to the unilateral behaviour of elements is obtained through an optimisation process, which is solved using a genetic algorithm. Each chromosome in the population having a negative fitness is a distinctive feasible solution with its own grouping characteristic, which is automatically determined throughout the evolution process.

The self-stress identification is formulated through an unconstrained minimisation problem. The objective function of this minimisation problem is defined in such a way that takes into account both the feasibility of a solution and grouping of elements. The method generates a set of feasible self-stress modes rather than a single one and automatically and simultaneously suggests a grouping of elements for every feasible self-stress mode. A self-stress mode with a minimal/subminimal grouping of elements is also obtained.

The method can efficiently generate sets of feasible solutions rather than a single one. The authors also address one of the challenging issues related to this identification, i.e., automated grouping of elements. These features makes the method very efficient since most of the state-of-the-art methods address the self-stress identification of tensegrities based on predefined groupings of elements whilst providing only a single corresponding solution.

Shell structures are highly efficient and are an elegant way of covering large uninterrupted spaces, but their complex geometry is notoriously difficult to model and analyse. This paper aims to describe a novel free-form shell modelling technique based on structural harmonics.

The method builds on work using weighted eigenmodes for three-dimensional mesh modelling in a computer graphics setting and extends it by specifically adapting the technique to an architectural design context. This not only enables the sculpting of free-form architectural surfaces using only a few control parameters but also takes advantage of the synergies between eigenmodes and structural buckling modes, to provide an efficient means of stiffening a shell against failure by buckling.

The result is a flexible free-form modelling tool that not only enables the creation of arbitrary doubly curved surfaces but also allows simultan. The tool helps to assist in the design of shells at the conceptual stage and encourages an interaction between the architect and engineer. A number of initiatives, including a single degree of freedom design, boundary constraints, visualisation aids and guidelines towards specific spatial configurations have been introduced to satisfactorily adapt the method to an architectural context.

The tool helps to assist in the design of shells at the conceptual stage and encourages an interaction between the architect and engineer. A number of initiatives, including a single degree of freedom design, boundary constraints, visualisation aids and guidelines towards specific spatial configurations have been introduced to satisfactorily adapt the method to an architectural context. This paper includes a full case study of the iconic British Museum Great Court Roof to demonstrate the applicability of the developed framework to real-world problems and the software developed to implement the method is available as an open-source download.

In this chapter, the authors ask two questions: (i) Is the conduct of monetary policy stable across time and similar across major economies? and (ii) Do policy decisions of major central banks have international spillover effects? To address these questions, the authors build on recent semi-parametric advances in time-varying parameter models that allow us to increase the vector autoregressive () dimension and to jointly model three advanced economies (USA, UK and the Euro Area). The main reduced-form finding of this chapter is an increased connectedness between and within countries during the recent financial crisis. In order to study policy spillovers, we jointly identify three economy-specific monetary policy shocks using a combination of sign and magnitude restrictions. The authors find that monetary policy shocks were larger in magnitude and more persistent in the early 1980s than in subsequent periods. The authors also uncover positive spillover effects of policy between countries in the 1980s and diminished, and sometimes negative ‘beggar-thy-neighbour’ effects in the second half of the sample. Moreover, during the 1980s, the authors find evidence for policy coordination between the Federal Reserve, the Bank of England and the European Central Bank.

This paper describes a parallel algorithm for the dynamic relaxation (DR) method. The basic theory of the dynamic relaxation is briefly reviewed to prepare the reader for the parallel implementation of the algorithm. Some fundamental parallel processing schemes have been explored for the implementation of the algorithm. Geometric Parallelism was found suitable for the DR method when using transputer‐based systems. The evolution of the parallel algorithm is given by identifying the steps which may be executed in parallel. The structure of the parallel code is discussed and then described algorithmically. Two geometrically non‐linear parallel finite element analyses have been performed using different mesh densities. The number of processors was varied to investigate algorithm efficiency and speed ups. Using the results obtained it is shown that the computational efficiency increases when the computational load per processor is increased.

This study aims to focus on a short review on recent results dealing with the mechanical modelling and experimental characterization of a novel class of tensegrity structures, named class θ = 1 tensegrity prisms. The examined structures exhibit six bars connected by two disjoint sets of strings.

First, the self-equilibrium problem of tensegrity θ = 1 prisms is numerically investigated for varying values of two aspect parameters and, next, their prestress stability is studied. The mechanical behavior of the examined structures in the large displacements regime under uniform compression loading is also numerically computed through a path-following procedure. Finally, the predicted constitutive response is validated through experimental tests.

The presented results highlight that the examined structures exhibit a large number of infinitesimal mechanisms from the freestanding configuration, and reveal that they exhibit tunable elastic response switching from stiffening to softening.

This multi-faceted elastic response is in agreement with previous literature results on the elastic response of minimal tensegrity prism, and suggests that such units can be usefully used as non-linear springs in next-generation tensegrity metamaterials.

The present study is based on finding the structural response of a tensile membrane structure (TMS) through deformation. The intention of the present research is to develop a basic understanding of reliability analysis and deflection behavior of a pre-tensioned TMS. The mean value first-order second-moment method (MVFOSM) method is used here to evaluate stochastic moments of a performance function with random input variables. Results suggest the influence of modulus of elasticity, the thickness of the membrane, and edge span length are significant for reliability based TMS design.

A simple TMS is designed and simulated by applying external forces (along with prestress), as a manifestation of wind and snow load. A nonlinear analysis is executed to evaluate TMS deflection, followed by calculating the reliability index. Parametric study is done to consider the effect of membrane material, thickness and load location. First-order second moment (FOSM) is used to evaluative the reliability. A comparison of reliability index is done and deflection variations from μ − 3s to μ + 3s are accounted for in this approach.

The effectiveness of deflection is highlighted for the reliability assessment of TMS. Reliability and parametric study collectively examine the proposed geometry and material to facilitate infield design requirements. The estimated β value indicates that most suitable fabric material for a simple TMS should possess an elasticity modulus in the range of 1,000–1,500 MPa, the thickness may be considered to be around 1.00 mm, and additional adjustment of around 5–10 mm is suggested for edge length. The loading position in case of TMS structures can be a sensitive aspect where the rigidity of the surface is dependent on the pre-tensioning of the membrane.

The significance of the parametric study on material and loading for deflection of TMS is emphasized. Due to the lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for researchers.

The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.

The significance of parametric study for serviceability criteria is emphasized. Parameters like pre-stress can be included in future parametric studies to witness in depth behavior of TMS. Due to lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for the researchers. The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.

The paper aims to present a framework for discussing ethics and computational design.

The main propositions of computational design are presented, discussed according to different authors and contrasted with cybernetic principles.

The paper finds that with algorithmic and parametric procedures, architects are using computation to reach a hitherto unknown ease of modelling multiple iterations of a design, so they can expand their possible design scenarios and cope with the uncertainties of ill-defined tasks. However, this strategy faces an ethical limitation because they fail to extend this openness to the final segment of the design chain, the user in the act of dwelling.

The paper brings a cybernetic perspective for discussing the often-overlooked ethical implications of computational strategies in design.