Precise scenarios - a customer-friendly foundation for formal specifications

A formal specification is beyond the comprehension of the average software customer. As a result, the customer cannot provide useful feedback regarding its correctness and completeness. To address this problem, we suggest the formalism expert to work with the customer to create precise scenarios. A precise scenario describes an operation by its effects on the system state with only few simple Z concepts. The customer would find a concrete precise scenario easier to understand than its corresponding abstract schema. The Z expert derives schemas based on the precise scenarios. Precise scenarios affords user involvement that improves the odds of a formal specification fully capturing the user requirements

Feasibility of a kneeling train to improve platform–train interface for passenger boarding and alighting

Railway operators and infrastructure companies strive to optimise the flow of passengers on and off vehicles whilst aiming to minimise accidents at the Platform-Train Interface (PTI). An ideal solution (already available in some situations) would be a step-free access to aid efficient boarding for everyday passengers and those with additional needs or reduced mobility. Out of many solutions existing today, a ‘kneeling vehicle’ seems a possible solution due to the opportunity to minimise the step and gap distances. In this paper, the viability of an assumed kneeling mechanism retro-fitted to a contemporary suspension architecture is assessed by evaluating the possible improvement in the step/gap distances based on a detailed model of suspension movement. It is shown that for many different infrastructure scenarios that significant improvements in the PTI are shown for a modest and achievable kneeling action. This paper also address fundamental operational concerns of a kneeling vehicle by assessing gauging (with respect to infrastructure and adjacent vehicles) and pantograph interaction

Additional file 3: of Integration of induced pluripotent stem cell-derived endothelial cells with polycaprolactone/gelatin-based electrospun scaffolds for enhanced therapeutic angiogenesis

Figure S3. showing (A) bioluminescence standard curve with upper limit of iPSC-EC concentration detection before IVIS camera saturation, inset. (B) Lower limit of iPSC-EC concentration detection after background/noise subtraction. n = 5 samples/group. (TIFF 44988 kb

Additional file 2: of Integration of induced pluripotent stem cell-derived endothelial cells with polycaprolactone/gelatin-based electrospun scaffolds for enhanced therapeutic angiogenesis

Figure S2. showing (A) analysis of iPSC-EC infiltration into scaffolds, representative photographs of scaffold cross-sections stained with DAPI. n = 100 cells/scaffold, scale bar represents 100 μm. (B) Young’s modulus and (C) ultimate tensile strength (UTS) of PG73 scaffolds before and after wetting. n = 5 samples/group. (D) Degradation rate of PG73 scaffolds compared to PCL over 4 days in an accelerated Protease XIV degradation solution. n = 3 samples/group. (TIFF 12785 kb

Additional file 1: of Integration of induced pluripotent stem cell-derived endothelial cells with polycaprolactone/gelatin-based electrospun scaffolds for enhanced therapeutic angiogenesis

Figure S1. showing (A) representative SEM photographs of PG73 and PG55 scaffolds before and after soaking in PBS for 7 days, scale bar represents 10 Îźm. (B) Scaffold cross-section images for porosity analysis. n = 5 samples/group, scale bar represents 100 Îźm. (TIFF 19523 kb

Additional file 4: of Integration of induced pluripotent stem cell-derived endothelial cells with polycaprolactone/gelatin-based electrospun scaffolds for enhanced therapeutic angiogenesis

Figure S4. showing (A) dedifferentiation of iPSC-ECs seeded on PG73 vs PCL scaffolds after 7 days culture in vitro. Photographs using (B) immunostains for CD31+ for endothelial phenotype and (C) vimentin+ for fibroblast phenotype. *p < 0.05. n = 3 samples/group, scale bar represents 40 Îźm. (TIFF 51787 kb