Optimised design of energy efficient building façades via Evolutionary Neural Networks

Buildings are required to be more and more energy efficient, in order to comply with restrictive requirements of building regulations and energy certifications. Optimisation algorithms have shown to be effective in identifying good solutions for the design of efficient building services. In this article Evolutionary Neural Network Design (ENN-Design) has been adopted to drive the design of a typical façade module for an office building. This application is significant, since façades play a major role in the definition of the energy performance of buildings. Both single-objective and multi-objective optimisations have been carried out. The aim of the article is to introduce an innovative approach for improving the performance of building envelopes by means of a reasonable amount of calculation time.     

Experimental investigation and optimisation in drilling of GFRP composites

Glass fibre-reinforced polymer (GFRP) composite materials are one of the important materials and are economic alternative to engineering materials because of their superior properties. This paper presents an effective approach for the optimisation of drilling parameters with multiple performance characteristics based on the Tagugch’s method with grey relational analysis. Taguchi’s L₁₆, 4-level orthogonal array has been used for the experimentation. The drilling parameters such as spindle speed and feed rate are optimised with consideration of multiple performance characteristics, such as thrust force, workpiece surface roughness and delamination factor. Response table and response graph are used for the analysis. The analysis of grey relational grade indicates that feed rate is the more influential parameter than spindle speed. The results indicate that the performance of drilling process can be improved effectively through this approach.     

Enhanced red emission in LiAl5O8:Fe phosphor by B doping

Fe³⁺, B³⁺ co-doping LiAl₅O₈ phosphor has been successfully synthesized by a solid-state reaction method assisted with wet chemical mixing route. Photoluminescence emission peak is observed at around 672 nm excited at both 290 nm ultraviolet and 565 nm green light. With introduction of a small amount of boric acid, the red emission intensity can be enhanced by 2.62 times under 290 nm excitation and 2.31 times under 565 nm excitation, respectively. It is believed that the substitution of B³⁺ ions for Al³⁺ sites decreases the symmetry of the luminescence center, intensifying the red emission.     

Global supply chain planning for pharmaceuticals

The shortening of patent life periods, generic competition and public health policies, among other factors, have changed the operating context of the pharmaceutical industry. In this work we address a dynamic allocation/planning problem that optimises the global supply chain planning of a pharmaceutical company, from production stages at primary and secondary sites to product distribution to markets. The model explores different production and distribution costs and tax rates at different locations in order to maximise the company's net profit value (NPV).Large instances of the model are not solvable in realistic time scales, so two decomposition algorithms were developed. In the first method, the supply chain is decomposed into independent primary and secondary subproblems, and each of them is optimised separately. The second algorithm is a temporal decomposition, where the main problem is separated into several independent subproblems, one per each time period. These algorithms enable the solution of large instances of the problem in reasonable time with good quality results.     

Effect of process parameters on the quality of aluminium alloy Al5Si deposits in wire and arc additive manufacturing using a cold metal transfer process

A 3D print device using a cold metal transfer arc welding station to melt a metallic filler wire is developed to build aluminium part by optimising the process parameters. First tests achieved using standard pre-recorded process parameters allow to study the effect of the travel speed and the average welding power on the geometrical characteristics of mono-layer deposits and on walls built by layers superposition. Finally, a parametric study of the effect of each process parameter controlling the shape of the arc current or voltage and the filler wire feeding is carried out in order to try to improve the geometrical regularity of the deposits, and to better understand the effect of each parameter on the melting of the filler wire, its transfer on the support plate, and the geometry of the formed bead.     

Optimisation models to enhance resilience in evacuation planning

We argue that the concepts of resilience in engineering science and robustness in mathematical optimisation are strongly related. Using evacuation planning as an example application, we demonstrate optimisation techniques to improve solution resilience. These include a direct modelling of the uncertainty for stochastic or robust optimisation as well as taking multiple objective functions into account.     

广东地区遗址博物馆展厅天窗优化设计初探

我国博物馆能源消耗巨大,在博物馆中合理设置采光天窗能有效降低照明能耗。遗址博物馆作为博物馆的一种类型,对其自然采光需求和遗址保护之间的矛盾亟需进一步研究。通过对广东地区遗址博物馆实地调研和对其中两个博物馆展厅的光环境测量,梳理了这一类型博物馆中展厅天窗导致局部出现眩光、整体照度过高或采光不均匀的采光现状,然后利用日光模拟软件VELUX Daylight Visualizer 2进行模拟分析,提出广东地区遗址博物馆展厅的天窗优化设计方法——天窗遮阳整合设计。例如全玻璃顶天窗设计可整合发光天棚、条形天窗可整合漫反射结构优化设计的策略,以期为广东地区遗址博物馆展厅天窗优化设计提供借鉴。     

Antoni Gaudí and Frei Otto: Essential Precursors to the Parametricism Manifesto

As Senior Architect to the Basilica of the Sagrada Família in Barcelona, Mark Burry has been ‘thinking parametrically’ for almost his entire career. Here he describes how his longstanding role overseeing the completion of Antoni Gaudí's masterpiece has afforded unique insights into the work of a great geometer and parametric thinker. Burry places the contribution of Gaudí alongside that of Frei Otto – the other eminent 20th-century Proto-Parametricist.     

SIMULATION AND SCALE-UP OF PNEUMATIC CONVEYING AND CASCADING ROTARY DRYERS

ABSTRACT

This paper presents a unified model for simulation of cocurrent and countercurrent dispersion-type dryers. The main industrial applications are to pneumatic conveying (flash) dryers and cascading (direct) rotary dryers. The basic model is a one-dimensional incremental (stepwise) simulation, which has been developed over a number of years Equations for particle motion, heat and mass transfer, heat and mass balances and local gas conditions are solved simultaneously over a small increment along the dryer. All workers have previously had considerable difficulty in obtaining a good fit between simulations and actual results from pilot-plants or large-scale industrial dryers. A new “fitting mode” calculation overcomes this by identifying the parameters which need to be adjusted, concentrating on those which cannot be measured accurately. Excellent agreement has been obtained between the model and experimental data by this method. The paper also presents revised formulations for particle motion and heat transfer in rotary dryers. The model has been incorporated into two computer programs for flash and rotary dryers respectively, and results from the former are shown for a case study.     

Fluid catalytic cracking optimisation using factorial design and genetic algorithm techniques

Statistical techniques coupled with genetic algorithm (GA) were used to identify optimal values of key operational variables in fluid catalytic cracking (FCC) process. A Kellog Orthoflow F fluid catalytic cracking process model was considered. It is known as a highly nonlinear process with a large number of variables with strong interactions among them. A reduced process model was obtained through factorial design technique to be used as a process function in the optimisation work giving as result the operational conditions that maximise conversion without infringing operational restrictions with savings in computational burden and time. An increase of 8.71% in process conversion was achieved applying GA as optimisation technique. © 2012 Canadian Society for Chemical Engineering