Benefit and performance impact analysis of using hydrogen fuel cell powered e-taxi system on A320 class airliner

This paper presents the work carried out to evaluate the benefits and performance impacts of introducing a hydrogen fuel cell powered electric taxiing system to a conventional short-haul aircraft. Tasks carried out in this research and reported in this paper include the initial system design, hydrogen tank initial sizing, calculation of the impact on fuel burn and emissions and the evaluation of the effects on Direct Operating Cost (DOC). The Airbus A320 has been selected as the datum aircraft for sizing the system, and the benefits analysis is particularly focused on the fleet composition and financial data of a Europe-based, low-cost, large-scale A320 family operator in 2016. The maximum power capacity of 400 kW has been sized based on the rolling friction coefficient of 0.02. Based on the operator’s 2016 financial, up to 1% fuel reduction can be achieved using the proposed system and the reduction in total maintenance cost is expected to be up to 7.3%. Additionally, up to 5.97% net profit improvement is estimated in comparison with the annual after-tax profit of the datum operator in 201

Metallic and Non-Metallic Plasmonic Nanostructures for LSPR Sensors

Localized surface plasmonic resonance (LSPR) provides a unique scheme for light management and has been demonstrated across a large variety of metallic nanostructures. More recently, non-metallic nanostructures of two-dimensional atomic materials and heterostructures have emerged as a promising, low-cost alternative in order to generate strong LSPR. In this paper, a review of the recent progress made on non-metallic LSPR nanostructures will be provided in comparison with their metallic counterparts. A few applications in optoelectronics and sensors will be highlighted. In addition, the remaining challenges and future perspectives will be discussed

Employing Symmetry Features for Automatic Misalignment Correction in Neuroimages

A novel method to automatically compute the symmetry plane and to correct the 3D orientation of neuro-images is presented. In acquisition of neuroimaging scans, the lack of perfect alignment of a patient's head makes it challenging to evaluate brain images. By deploying a shape-based criterion, the symmetry plane is defined as a plane that best matches external surface points on one side of the head, with their counterparts on the other side. In our method, the head volume is represented as a re-parameterized surface point cloud, where each location is parameterized by its elevation (latitude), azimuth (longitude), and radius. The search for the best matching surfaces is implemented in a multi-resolution paradigm, and the computation time is significantly decreased. The algorithm was quantitatively evaluated using in both simulated data and in real T1, T2, Flair magnetic resonance patient images. This algorithm is found to be fast (< 10s per MR volume), robust and accurate (< .6 degree of Mean Angular Error), invariant to the acquisition noise, slice thickness, bias field, and pathological asymmetries

Automatic Misalignment Correction in Neuroimages Using Surface Symmetry Priors

Many brain imaging procedures require the careful alignment of different sets of images obtained in the same individual. The available automatic methods for brain alignment are susceptible to improvement. This paper discusses briefly a new automatic method to reinstall the tilted orientation of head images, using surface symmetry as a prior

The potential use of BIM to aid construction waste minimalisation

It is widely acknowledged that the construction industry has a major impact on the environment, both in terms of resource consumption and waste production. The construction industry is responsible for producing a whole variety of different onsite wastes; the amount and type of which depends on factors such as the stage of construction, type of construction work, direct or indirect stakeholders’ design change contribution, and practices throughout the project lifecycle. A number of construction waste minimisation (CWM) techniques and tools are currently available to assist contractors to divert waste away from landfill. However, literature reveals that there are insufficient techniques and tools for reducing construction waste during the design and procurement stages. The last few years saw the emergence of Building Information Modelling (BIM) techniques, which can be adopted to improve sustainable construction performance. BIM is a maturing modelling philosophy, which has been applied to several building-related functions such as visualising designs, automating quantity takeoffs, checking compliance with regulations, and scheduling construction processes. Furthermore, BIM, as a real-time interactive and collaborative communication system, has the potential to help project stakeholders to collaboratively attain waste minimisation for sustainable construction and building throughout design, construction and throughout the lifecycle by improving building construction performance. Hence, this paper, which is part of an ongoing doctoral study, explores the potential application of BIM to design out waste. An in-depth literature review was conducted to provide a foundation for the doctoral study that aims to investigate the use of BIM as a potential platform for building design waste minimisation. The paper explores construction waste origins and causes, current waste reduction practices; examines current industry BIM practices and investigates BIM tools for sustainable project construction and management; and identifies the knowledge gaps in existing literature that pave the way for the subsequent data collection stages

Direct observation of nucleation in the bulk of an opaque sample

Remarkably little is known about the physical phenomena leading to nucleation of new perfect crystals within deformed metals during annealing, in particular how and where volumes with nearly perfect lattices evolve from structures filled with dislocations, and how local variations at the micrometer length scale affect this nucleation process. We present here the first experimental measurements that relate directly nucleation of recrystallization to the local deformation microstructure in the bulk of a sample of cold rolled aluminum, further deformed locally by a hardness indentation. White beam differential aperture X-ray microscopy is used for the measurements, allowing us to map a selected gauge volume in the bulk of the sample in the deformed state, then anneal the sample and map the exact same gauge volume in the annealed state. It is found that nuclei develop at sites of high stored energy and they have crystallographic orientations from those present in the deformed state. Accordingly we suggest that for each nucleus the embryonic volume arises from a structural element contained within the voxels identified with the same orientation. Possible nucleation mechanisms are discussed and the growth potentials of the nuclei are also analyzed and discussed