Innovative Multiple Matching Charts approach to support the conceptual design of hypersonic vehicles

Several well-established best practices and reliable tools have been developed along the years to support aircraft conceptual and preliminary design. In this context, one of the most widely used tool is the Matching Chart (MC), a graphical representation of the different performance requirements (curves representing the thrust-to-weight ratio (T/W) requirement as function of the wing loading (W/S)) for each mission phase. The exploitation of this tool allows the identification of a feasible design space as well as the definition of a reference vehicle configuration in terms of maximum thrust, maximum take-off weight, and wing surface since the very beginning of the design process. Although the tool was originally developed for conventional aircraft, several extensions and updates of the mathematical models have been proposed over the years to widen its application to innovative configurations. Following this trend, this paper presents a further evolution of the MC model to support the conceptual design of high-speed transportation systems, encompassing supersonic and hypersonic flight vehicles. At this purpose, this paper reports and discusses the updates of the methodology laying behind the generation of the MC for high-speed transportation. Eventually, the results of the validation of the updated methodology and tool are reported, using as case study, the STRATOFLY MR3 vehicle configuration, a Mach 8 antipodal civil transportation system, currently under development within the H2020 STRATOFLY project

Propellant subsystem design for hypersonic cruiser exploiting liquid hydrogen

The possibility of establishing a new paradigm for commercial aviation towards high-speed flight in the next decades shall be inevitably preceded by the increase of Technology Readiness Level for those relevant enabling technologies associated to propulsion, thermal management and on-board subsystems, with particular attention also to environmental sustainability and economic viability of the proposed concepts. New design methodologies for both aircraft and on-board subsystems design shall then be based on holistic approaches able to catch the strong interactions between vehicle configuration, mission and subsystems architecture, which characterize high-speed aircraft layouts. This paper proposes a methodology for the preliminary sizing of propellant subsystems for liquid hydrogen powered hypersonic cruisers. Making benefit of traditional approaches, the process aims at introducing new design aspects directly connected to the peculiar multifunctional architecture of on-board subsystems for high-speed vehicles, so to be able to include additional analyses in early design stages, especially in case of high level of on-board integration. Notably, impact of requirements for Center of Gravity control, thermal, and, in general, energy management are considered as integral part of the method, with crucial implications on architecture selection. After the introduction of design algorithms for subsystem sizing, the STRATOFLY MR3 hypersonic cruiser is taken as reference case study in order to provide a practical example of application of the proposed approach on a highly integrated platform

Cost estimation methodology and tool for future Reusable Access To Space Systems

This paper aims at presenting the latest upgrades to HyCost Methodology and Tool, developed by Politecnico di Torino under funding and supervision of the European Space Agency (ESA), to support Life Cycle Cost (LCC) estimation of reusable access to space vehicles. The main idea is to support engineers in cost estimation activities during conceptual and preliminary design phases, allowing for the evaluation of Research, Development, Test and Evaluation (RDTE) Costs, Production Costs, as well as Direct and Indirect Operating Costs (DOC and IOC), for a wide set of high-speed aerospace systems. Politecnico di Torino has already disclosed a LCC methodology and tool specifically tailored to air-breathing high-speed transportation systems. Complementary, this paper discloses the methodology upgrades to extend the methodology and tool capabilities to future Reusable Access to Space Vehicles. At first, the applicability of already existing parametric cost estimation relationships (CERs) to the peculiarities of Reusable Access to Space Vehicles is assessed and then, when necessary, new parametric equations are defined. Specifically, the new set of equations is considered fundamental to capture the impact of different vehicle configurations (e.g. staging strategy, staging Mach number, parallel or series configuration, etc…) onto costs, as well as the impact of the most promising propulsive solutions, ranging from scramjet and combined cycle engines to rocket engines. Ultimately, the upgraded methodology is validated against the available SpaceX Starship cost data

A methodology for preliminary sizing of a Thermal and Energy Management System for a hypersonic vehicle

This paper addresses a methodology to parametrically size thermal control subsystems for high-speed transportation systems during the conceptual design phase. This methodology should be sufficiently general to be exploited for the derivation of Estimation Relationships (ERs) for geometrically sizing characteristics as well as mass, volume and power budgets both for active (turbopumps, turbines and compressors) and passive components (heat exchangers, tanks and pipes). Following this approach, ad-hoc semi-empirical models relating the geometrical sizing, mass, volume and power features of each component to the operating conditions have been derived. As a specific case, a semi-empirical parametric model for turbopumps sizing is derived. In addition, the Thermal and Energy Management Subsystem (TEMS) for the LAPCAT MR2 vehicle is used as an example of a highly integrated multifunctional subsystem. The TEMS is based on the exploitation of liquid hydrogen boil-off in the cryogenic tanks generated by the heat load penetrating the aeroshell throughout the point-to-point hypersonic mission. Eventually, specific comments about the results will be provided together with suggestions for future improvements

Drug resistance in B and non-B subtypes amongst subjects recently diagnosed as primary/recent or chronic HIV-infected over the period 2013–2016: Impact on susceptibility to first-line strategies including integrase strand-transfer inhibitors

Objectives To characterize the prevalence of transmitted drug resistance mutations (TDRMs) by plasma analysis of 750 patients at the time of HIV diagnosis from January 1, 2013 to November 16, 2016 in the Veneto region (Italy), where all drugs included in the recommended first line therapies were prescribed, included integrase strand transfer inhibitors (InNSTI). Methods TDRMs were defined according to the Stanford HIV database algorithm. Results Subtype B was the most prevalent HIV clade (67.3%). A total of 92 patients (12.3%) were expected to be resistant to one drug at least, most with a single class mutation (60/68–88.2% in subtype B infected subjectsand 23/24–95.8% in non-B subjects) and affecting mainly NNRTIs. No significant differences were observed between the prevalence rates of TDRMs involving one or more drugs, except for the presence of E138A quite only in patients with B subtype and other NNRTI in subjects with non-B infection. The diagnosis of primary/recent infection was made in 73 patients (9.7%): they had almost only TDRMs involving a single class. Resistance to InSTI was studied in 484 subjects (53 with primary-recent infection), one patient had 143C in 2016, a total of thirteen 157Q mutations were detected (only one in primary/recent infection). Conclusions Only one major InSTI-TDRM was identified but monitoring of TDRMs should continue in the light of continuing presence of NNRTI-related mutation amongst newly diagnosed subjects, sometime impacting also to modern NNRTI drugs recommended in first-line therapy

A methodology for preliminary sizing of a Thermal and Energy Management System for a hypersonic vehicle

This paper addresses a methodology to parametrically size thermal control subsystems for high-speed transportation systems. This methodology should be sufficiently general to be exploited for the derivation of Estimation Relationships (ERs) for geometrically sizing characteristics as well as mass, volume and power budgets both for active (turbopumps, turbines and compressors) and passive components (heat exchangers, tanks and pipes). Following this approach, ad-hoc semi-empirical models relating the geometrical sizing, mass, volume and power features of each component to operating conditions have been derived. As a specific case, a semi-empirical parametric model for turbopumps sizing is derived. In addition, the Thermal and Energy Management Subsystem (TEMS) for the LAPCAT MR2 vehicle is used as an example of a highly integrated multifunctional subsystem. The TEMS is based on the exploitation of liquid hydrogen boil-off in the cryogenic tanks generated by the heat load penetrating the aeroshell, all along the point-to-point hypersonic mission. Eventually, specific comments about the results will be provided together with suggestions for future improvements

Mega-Events: Assessing Road Safety through an Operating Framework. An Application for the Milano–Cortina 2026 Winter Olympic Games †

To meet the United Nations and European Union goals of reducing road crash fatalities and injuries, it is also relevant to address the negative externalities due to mega-events on the road network and the local communities, to assess the safety of the road network involved, and to implement appropriate measures for different road environments. Despite their relevance, the literature often overlooks social costs and risks associated with mega-events. This study presents an operating framework for rapidly assessing the safety of the Milano–Cortina 2026—“Via Olimpica” road—which will host a significant proportion of the traffic during the Winter Olympic Games in 2026. The framework proposes a simplified Road Infrastructure Safety Management (RISM) to address the unique challenges posed by the limited time available for screening and implementation by local authorities. The framework integrates four data sources and follows a seven-step procedure. It provides recommendations for improving road safety by identifying critical road sections and blackspots. Road authorities, practitioners, and public administrations may all benefit from the framework, as it makes it easier to prioritise safety improvements within time constraints

Tick-borne encephalitis in north-east Italy: a 14-year retrospective study, January 2000 to December 2013

Italy is considered at low incidence of tick-borne encephalitis (TBE), and the occurrence of human cases of TBE appears to be geographically restricted to the north east of the country. However, most information to date derives from case series, with no systematic data collection. To estimate incidence rates (IR) and spatial distribution of TBE cases, we conducted a retrospective study in north-eastern Italy. Data were collected through the infectious disease units and public health districts of three regions (Friuli Venezia Giulia, Trentino Alto Adige and Veneto) between 2000 and 2013. Overall, 367 cases were identified (IR: 0.38/100,000). The cases' median age was 56 years and 257 (70%) were male. Central nervous system involvement was reported in 307 cases (84%). Annual fluctuations in case numbers occurred, with peaks in 2006 and in 2013, when 44 and 42 cases were respectively observed. A strong seasonality effect was noted, with the highest number of cases in July. In terms of geographical location, three main endemic foci with high TBE IR (> 10/100,000) were identified in three provinces, namely Belluno (Veneto region), Udine (Friuli Venezia Giulia) and Trento (Trentino Alto-Adige). When investigating the whole study area in terms of altitude, the IR between 400 and 600\u2009m was greater (2.41/100,000) than at other altitudes (p< 0.01). In conclusion, the incidence of TBE in Italy is relatively low, even considering only the three known affected regions. However, three endemic foci at high risk were identified. In these areas, where the risk of TBEV infection is likely high, more active offer of TBE vaccination could be considere

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured