Search

In the German LuFo research project AVACON, the project partners jointly developed a mid-range aircraft concept for the year 2028 with an over-wing engine configuration. With every new iteration of the initial concept, an adapted cabin concept was derived. This paper introduces the different cabin concept derivatives and assesses them regarding their boarding performance. The assessment is performed using the PAXelerate open-source boarding simulation framework. The results for a random boarding simulation show a boarding time reduction potential of 3.4 percent for the adapted cabin layouts of the iterated cabin design. The COVID-19 crisis has forced severe limitations on the international transportation market and has put a focus on the infection risk within the aircraft cabin. Thus, this paper introduces as a second aspect a new methodology that enables PAXelerate to assess the individual COVID-19 exposure risk of passengers during the boarding process. The basic model enhancement consists of the tracking of all passenger movements throughout the cabin, the determination of the proximity to other passengers as well as the monitoring of the duration of the individual contacts. This approach is similar to the frameworks introduced by Apple and Google for contact tracing on smart phones. The results highlight the overall risk for rear-to-front and front-to-rear boarding scenarios, considering the overall number of contacts as well as the proximity and duration of individual passenger contacts. Boarding scenarios such as window-to-aisle, random or the so-called Steffen procedure seem beneficial. The removal of cabin luggage has the largest effect on exposure risk mitigation. This highlights potential pathways for a future safe travel scenario with a minimized exposure risk for all passengers.

The cabin is a crucial aspect of today's and future aircraft as it is the single most important element passengers are in contact with during a flight. It is thus increasingly important to get an in-depth impression of the layout, even during early design phases. However, in the current preliminary aircraft design process, 2D methods and cabin representations are common. This paper introduces a novel fast way to assess and visualize a cabin by displaying it in three dimensions. This enables a deeper understanding of a cabin during the early design phases by providing advanced assessment possibilities as well as visualization capabilities for photorealistic renders, animations and VR experiences. The foundation for the model is the cabin and fuselage design environment (CAFE) of PAXelerate. In combination with the CPACS support, it enables a swift and easy cabin design process. With the help of the open source 3D creation suite Blender, the 2D cabin layout is translated into a detailed 3D cabin and fuselage geometry, which can then be further used for high quality renderings and cabin geometry post processing. This includes 3D object collision detection, the verification of safety zone and evacuation area sizing as well as a cabin volume calculation. This rapid automated 3D cabin generation tool enables new possibilities for the cabin design during the preliminary aircraft design process by adding a third dimension and by providing an easy and fast way for photorealistic cabin renderings, VR experiences and a cabin assessment not possible using 2D methods. By using this approach, novel cabin concepts can thus be experienced from a completely different angle, benefiting both passengers and manufacturers of future aircraft.

BackgroundTissue inflammation in inflammatory bowel diseases (IBD) is associated with a decrease in local pH. The gene encoding G-protein-coupled receptor 65 (GPR65) has recently been reported to be a genetic risk factor for IBD. In response to extracellular acidification, proton activation of GPR65 stimulates cAMP and Rho signalling pathways. We aimed to analyse the clinical and functional relevance of the GPR65 associated single nucleotide polymorphism (SNP) rs8005161.Methods1138 individuals from a mixed cohort of IBD patients and healthy volunteers were genotyped for SNPs associated with GPR65 (rs8005161, rs3742704) and galactosylceramidase (rs1805078) by Taqman SNP assays. 2300 patients from the Swiss IBD Cohort Study (SIBDC) were genotyped for rs8005161 by mass spectrometry based SNP genotyping. IBD patients from the SIBDC carrying rs8005161 TT, CT, CC and non-IBD controls (CC) were recruited for functional studies. Human CD14+ cells were isolated from blood samples and subjected to an extracellular acidic pH shift, cAMP accumulation and RhoA activation were measured.ResultsIn our mixed cohort, but not in SIBDC patients, the minor variant rs8005161 was significantly associated with UC. In SIBDC patients, we observed a consistent trend in increased disease severity in patients carrying the rs8005161-TT and rs8005161-CT alleles. No significant differences were observed in the pH associated activation of cAMP production between IBD (TT, CT, WT/CC) and non-IBD (WT/CC) genotype carriers upon an acidic extracellular pH shift. However, we observed significantly impaired RhoA activation after an extracellular acidic pH shift in IBD patients, irrespective of the rs8005161 allele.ConclusionsThe T allele of rs8005161 might confer a more severe disease course in IBD patients. Human monocytes from IBD patients showed impaired pH associated RhoA activation upon an acidic pH shift.

In the LuFo research project "AdVanced Aircraft CONcepts" (AVACON), one of the areas of interest is the aircrafts cabin layout as well as its implication on the passenger flow during the boarding procedure. Starting with the research baseline aircraft and continuing with each of the research projects consecutive aircraft derivations, a dedicated work package comprising of Airbus and Bauhaus Luftfahrt e.V. (BHL) assesses those questions. The specific task of BHL in this package is to assess the boarding process of the different aircraft iterations using the PAXelerate boarding simulation tool. PAXelerate2 is an open source, 2D agent-based passenger flow simulation developed by BHL as a fast way to assess novel cabin layouts in terms of their boarding performance. The foundation of the simulation framework is a cheapest path A-Star algorithm operating in a grid based cabin representation. Support for the CPACS file format is implemented into PAXelerate for the AVACON project in order to achieve a seamless import and integration of the different aircraft iterations. The tool itself consists of two parts with one being the cabin configurator module, which renders the CPACS data and enables the verification of implementations and a modification of the cabin layout. The simulation itself is executed in the second, console based module, enabling a rapid batch simulation and trade study assessment. In the scope of this publication, the passenger flow is simulated for the AVACON research baseline aircraft containing 252 passengers in a two-class layout. The assessment focuses on a variation of the applied boarding procedure (including a random, window-to-aisle sequence) as well as the respective door configuration. PAXelerate performs these different boarding scenarios and is capable of highlighting potential sensitivities. The results of the simulations not only deliver an average boarding time for a given scenario but also hint at other aspects such as the number of interruptions of passengers walking through the cabin. From this data, possible paths for a suitable boarding procedure as well as the impact of a different boarding door can be derived and highlight the path for the projects future cabin design.

The saving of energy has been an important topic for the last years. However, not only for building constructions but also in the field of naval architecture the energy revolution affected the used materials. Insulation glass units (IGU) are used on ships, because of their increased thermal insulation value, but their known problem of durability remains. Already after a few years, naval insulating glass units fog up on the inner site of the glass panes and get unusable. The insulating glass units are exposed to higher stress in the naval environment compared with building constructions. We have to consider comparatively high wind loads that results in thick glass packages. The dead weight of the outer panes are usually transferred via the edge sealant. Structural Sealant Glazing Systems (SSGS) without mechanical self-weight support are commonly used. Furthermore, there is the contact with saline water and high UV-radiation. Because of the movement of the ships around the world, the climatic load assumptions for stationary buildings do not apply. All these loads cause a pillow effect and stress the edge sealant to a point of an increased moisture transfer into the cavity. We conducted two-month artificial ageing tests according to DIN EN 1279-2. The experimental investigation included 67 insulating glass units and reference specimens, which are composed of 4 mm fully tempered glass and 12 mm cavity between the panes. The scope included bent and connected spacers, a variety of secondary sealant systems with an emphasis on novel permanent pressure equalisation structures. After the tests, it was possible to compare the moisture penetration of different edge sealant systems. Furthermore, we compared the aged with reference insulating glass units. We used these data to analyse the impact of the artificial ageing program on the sealants durability. The experimental investigation shows that the climatic loads have a strong influence on the gas transfer through the edge sealants of the insulating glass units. Systems, which enable the insulating glass unit to connect the gas cavity with the ambient air, absorb less moisture compared with reference systems. The results will allow us to evolve more durable sealant systems. Additionally, we can optimise the artificial ageing program for marine glazing products., Challenging Glass Conference Proceedings, Vol. 5 (2016): Challenging Glass 5