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The genetic algorithm (GA) technique is widely used for the optimization of stiffened composite panels. It is based on sequential execution of a number of specific operators, including the encoding of particular design variables. For instance, in the case of a stiffened composite panel, the design variables that need to be encoded are: the number of plies and their stacking sequences in the panel skin and stiffeners. This paper aims to present a novel, implicit, heuristic approach for encoding composite laminates and, through its use, demonstrates an improvement in the optimization process.

The stiffened panel optimization has been formulated as a constrained discrete minimum-weight design problem. GAs, which use both new encoding schemes and those previously described in the literature, have been used to find near-optimal solutions to the formulated problem. The influence of the new encoding scheme on the searching capabilities of the GA has been investigated using comparative analysis of the optimization results.

The new encoding scheme allows the definition of stacking sequences in composites using shorter symbolic representations as compared with standard encoding operators and, as a result of this, a reduction in the problem design space. According to numerical experiments performed in this work, this feature enables GA to obtain near-optimal designs using smaller population sizes than those required if standard encoding schemes are used.

The approach to encoding laminates presented in this paper is based on the original heuristics. In the context of GA-based optimization of stiffened composite panels, the use of the new approach rather than the standard encoding technique can lead to a significant reduction in computational time employed.

Conventional motion mechanisms in adaptive skins require rigid kinematic mechanical systems that require sensors and actuation devices, hence impeding the adoption of zero-energy buildings. This paper aims to exploit wooden responsive actuators as a passive approach for adaptive facades with dynamic shading configurations. Wooden passive actuators are introduced as a passive responsive mechanism with zero-energy consumption.

The study encodes the embedded hygroscopic parameters of wood through 4D printing of wooden composites as a responsive wooden actuator. Several physical experiments focus on controlling the printed hygroscopic parameters based on the effect of 3D printing grain patterns and infill height on the wooden angle of curvature when exposed to variation in humidity. The printed hygroscopic parameters are applied on two types of wooden actuators with difference in the saturation percentage of wood in the wooden filaments specifically 20% and 40% for more control on the angle of curvature and response behavior.

The study presents the ability to print wooden grain patterns that result in single and double curved surfaces. Also, printing actuators with variation in infill height control each part of wooden actuator to response separately in a controlled passive behavior. The results show a passive programmed self-actuated mechanism that can enhance responsive façade design with zero-energy consumption through utilizing both material science and additive manufacturing mechanisms.

The study presents a set of controlled printed hygroscopic parameters that stretch the limits in controlling the response of printed wood to humidity instead of the typical natural properties of wood.

In the reliability assessment of composite laminate structures with multiple components, the uncertainty space defined around design solutions easily becomes over-dimensioned, and not all of the random variables are relevant. The purpose of this study is to implement the importance analysis theory of Sobol’ to reduce the dimension of the uncertainty space, improving the efficiency toward global convergence of evolutionary-based reliability assessment.

Sobol’ indices are formulated analytically for implicit structural response functions, following the theory of propagation of moments and without violating the fundamental principles presented by Sobol’. An evolutionary algorithm capable of global convergence in reliability assessment is instrumented with the Sobol’ indices. A threshold parameter is introduced to identify the important variables. A set of optimal designs of a multi-laminate composite structure is evaluated.

Importance analysis shows that uncertainty is concentrated in the laminate where the critical stress state is found. Still, it may also be reasonable in other points of the structure. An accurate and controlled reduction of the uncertainty space significantly improves the convergence rate, while maintaining the quality of the reliability assessment.

The theoretical developments assume independent random variables.

Applying Sobol’ indices as an analytical dimension reduction technique is a novelty. The proposed formulation only requires one adjoint system of equilibrium equations to be solved once. Although a local estimate of a global measure, this analytical formulation still holds because, in structural design, uncertainty is concentrated around the mean-values.

Although conformable devices are commonly designed to couple with the human body for personalized and localized medicine, their applications are expanding rapidly. This paper aims to delineate this expansion and predict greater implications in diverse fields.

Today’s device technologies continue to face fundamental obstacles preventing their seamless integration with target objects to effectively access, evaluate and alter self-specific physical patterns, while still providing physical comfort and enabling continuous data collection. Due to their extreme mechanical compliance, conformable devices permit the query of signals occurring at interfaces so as to decode and encode biological, chemical and mechanical patterns with high resolution, precision and accuracy. These unique and versatile capabilities allow for a marked change in the approach to tackling scientific questions, with the ability to address societal challenges at large.

Here, this study highlights the current state of these devices in a wide range of fields, such as interactive teaching, textiles, robotics, buildings and infrastructure, agriculture, climate and space, and further forecasts essential features of these devices in the near future.

This study justifies conformable devices’ growing utility through a novel quantitative analysis methodology that indexes peer-reviewed journal articles based on specific keywords, whereby this study tracks keyword frequency over time across specific fields in conjunction with conformability-like topics. The resulting trends’ trajectories provide the foundation for this study’s future projections. This study concludes with a perspective on the possible challenges concomitant with a ubiquitous presence of these technologies, including manufacturing, wireless communication, storage, compression, privacy and sharing of data, environmental sustainability, avoidance of inequality and bias and collaboration between stakeholders at all levels of impact.

THE future of carbon fibre laminates in high‐tech industries such as aerospace receives a substantial boost by the development of an advanced 10‐axis computer controlled ultra‐sonic scanning machine designed and manufactured by the UK metrology specialist LK Ltd.

The failure of copper‐plated holes in dielectric laminates during thermal cycling is a serious problem for the electronics industry. The large difference in out‐of‐plane thermal expansion between the dielectric laminate and the copper plating can cause the copper plating to deform and fail as the board is thermally cycled. The purpose of this study was to demonstrate the feasibility of using electro‐optic holographic interferometry (EOHI) to measure deformation around plated holes and to evaluate methods for estimating the stress in the barrel plating. It was demonstrated that EOHI was more than adequate to resolve the out‐of‐plane thermally induced displacement field around an array of plated‐through holes. The displacement sensitivity was better than ±10 nm with high spatial resolution (92 ?m horizontally and 75 ?m vertically).The expansion was reasonably linear from 30°C to 120°C. The deformation around the individual holes was not axisymmetric. It is suggested that the method for estimating barrel stresses may be too sensitive to thickness and architecture variations in the pad for reliable stress estimates. An alternative scheme for estimation of barrel stresses based on thermal strain energy evaluation is described.

Looks at the eighth published year of the ITCRR and the research, from far and near, involved in this. Muses on the fact that, though all the usual processes are to the fore, the downside part of the industry is garment making which is the least developed side. Posits that the manufacture of clothing needs to become more technologically advanced as does retailing. Closes by emphasising support for the community in all its efforts.

THE Farnborough 1966 Show was at first glance much the same mixture as before, but the second glance was the more revealing. The participation in the flying display of European aircraft by no means swamped the air, even if the Italian verve took the acrobatic honours, but the theme of collaboration with other countries was to be found on practically every stand inside the exhibition tent. It was obvious that the smaller firms not directly involved in production agreements with other nations were very export conscious. The pacemaker of all this collaboration was of course the Concorde, only to be seen in model form, but rapidly taking shape at Toulouse and Filton, and many of the equipment manufacturers had Concorde hardware on display. Beagle announced the Pup, Britten‐Norman produced the production Islander, and Handley Page showed the Jetstream mock‐up. After many years of neglect, the industry is now taking an interest in the general aviation market. The P.1127 (R.A.F.) made its first appearance. The paradox of the P.1127 is that it is almost a part of Farnborough history, yet there is no other V/S.T.O.L. aircraft in the world that has but a fraction of the operating experience it has gained. Farnborough this year gave the impression of being more a serious trade show, and less a public spectacle. Sir Richard Smeeton, Director of the Society of British Aerospace Companies, reported that the exhibiting firms had received more serious business enquiries this year than ever before, and he forecast that 1968 would be a vintage year, which would see the appearance of the HS.801, the Concorde and Jaguar in the Farnborough skies. It is not possible to cover every exhibit shown at the Farnborough Show, but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

purpose of this paper is providing a solution for flexible flow shop scheduling problem with uncertain processing time in aeronautical composite lay-up workshop.

A flexible flow scheduling model and algorithm with interval grey processing time is established. First, according to actual needs of composite laminate shop scheduling process, interval grey number is used to represent uncertain processing time, and interval grey processing time measurement method, grey number calculation and comparison rules, grey Gantt chart, and other methods are further applied. Then a flexible flow shop scheduling model with interval grey processing time (G-FFSP) is established, and an artificial bee colony algorithm based on an adaptive neighbourhood search strategy is designed to solve the model. Finally, six examples are generated for simulation scheduling, and the efficiency and performance of the model and algorithm are evaluated by comparing the results.

Results show that flexible flow shop scheduling model and algorithm with interval grey processing time can provide an optimal solution for composite lay-up shop scheduling problems and other similar flow shop scheduling problems.

Uncertain processing time is common in flexible workshop manufacturing, and manual scheduling greatly restricts the production efficiency of workshop. In this paper, combined with grey system theory, an intelligent algorithm is used to solve flexible flow shop scheduling problem to promote intelligent and efficient production of enterprises.

This paper applies and perfects interval grey processing time measurement method, grey number calculation and comparison rules, grey Gantt chart and other methods. A flexible flow shop scheduling model with interval grey processing time is established, and an artificial bee colony algorithm with an adaptive domain search strategy is designed. It provides a comprehensive solution for flexible flow shop scheduling with uncertain processing time.

Genetic algorithm (GA) is a model of machine learning. The algorithm can be used to find sub‐optimum, if not optimum, solution(s) to a particular problem. It explores the solution space in an intelligent manner to evolve better solutions. The algorithm does not need any specific programming efforts but requires encoding the solution as strings of parameters. The field of application of genetic algorithms has increased dramatically in the last few years. A large variety of possible GA application tools now exist for non‐computer specialists. Complicated problems in a specific optimization domain can be tackled effectively with a very modest knowledge of the theory behind genetic algorithms. This paper reviews the technique briefly and applies it to solve some of the optimization problems addressed in construction management literature. The lessons learned from the application of GA to these problems are discussed. The result of this review is an indication of how the GA can contribute in solving construction‐related optimization problems. A summary of general guidelines to develop solutions using this optimization technique concludes the paper.