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1 – 10 of 10Roberta Fusaro and Nicole Viola
This paper aims to propose a methodology for a safety and reliability assessment for the conceptual and preliminary design of very complex and disrupting innovative systems like…
Abstract
Purpose
This paper aims to propose a methodology for a safety and reliability assessment for the conceptual and preliminary design of very complex and disrupting innovative systems like trans-atmospheric vehicles. The proposed methodology differs from existing ones because it does not rely on statistical data at aircraft-level but exploits the statistical population at components-level only. For the sake of clarity, the paper provides some preliminary results of the application of the methodology at system level. The example deals with the safety and reliability assessment of a very complex propulsion system aimed at guaranteeing vertical take-off and landing capabilities of a suborbital vehicle.
Design/methodology/approach
The proposed methodology is strongly based on a systems engineering approach. It exploits safety and reliability assessment analyses which have already been developed in both aeronautical and space engineering domains, but it combines them in an innovative way to overcome the lack of statistics at aircraft level. The methodology consists of two different steps: a qualitative top-down process, allowing a functional and physical decomposition of the transportation system and a following quantitative bottom-up approach, which provides the estimation of system-level reliability and safety characteristics starting from the statistical estimation of the components’ characteristics.
Findings
The paper presents a new methodology for the preliminary reliability and safety assessment of innovative transportation systems, such as hypersonic transportation systems. The envisaged methodology will overcome the poorness of statistical data that is usually affecting the conceptual design of breakthrough systems.
Research limitations/implications
The paper shows the application of the articulated methodology to a limited case study. A complete example of application of the methodology to estimate safety and reliability characteristics at vehicle level will be provided in feature works.
Practical implications
The methodology has been proposed to be exploited in international research activities in the field of hypersonic transportation systems. Furthermore, a massive application of this approach would allow to create a database for the generation and the update of semi-empirical models focused on high-level estimations of reliability, availability, maintainability and safety (RAMS) characteristics. Moreover, the proposed safety assessment has been conceived to be fully integrated within a typical conceptual design process.
Originality/value
The existing literature about safety and reliability assessment at the early design stages proposes pure statistical approaches which are usually not applicable to highly innovative products, where the statistical population is not existing, for example, in the case of trans-atmospheric vehicles. This paper describes how to overcome this problem, through the exploitation of statistical data at components-level only through the combination of these data to estimate RAMS characteristics at aircraft-level thanks to functional analysis, concept of operations and typical safety assessment tools, like functional hazard analysis, failure mode and effect analysis, reliability block diagram and fault tree analysis.
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Roberta Fusaro, Nicole Viola, Sara Cresto Aleina and Giovanni Antonio Di Meo
This paper aims to suggest feasible solutions to overcome the problem of unmanned aerial vehicles integration within the existing airspace.
Abstract
Purpose
This paper aims to suggest feasible solutions to overcome the problem of unmanned aerial vehicles integration within the existing airspace.
Design/methodology/approach
It envisages innovative time-based separation procedures that will enhance the integration in the future air traffic management (ATM) system of next generation of large remotely piloted aircraft system (RPAS). 4D navigation and dynamic mobile area concepts, both proposed in the framework of Single European Sky ATM Research program, are brought together to hypothesize innovative time-based separation procedures aiming at promoting integration of RPAS in the future ATM system.
Findings
Benefits of proposed procedures, mainly evaluated in terms of volume reduction of segregated airspace, are quantitatively analyzed on the basis of realistic operational scenarios focusing on monitoring activities in both nominal and emergency conditions. Eventually, the major limits of time-based separation for RPAS are investigated.
Practical implications
The implementation of the envisaged procedures will be a key enabler in RPAS integration in future ATM integration.
Originality/value
In the current ATM scenario, separation of RPAS from air traffic is ensured by segregating a large amount of airspace areas with fixed dimensions, dramatically limiting the activities of these vehicles.
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Giovanni Medici, Nicole Viola, Sabrina Corpino and Marco Fioriti
The purpose of this paper is to describe the tool and procedure developed in order to design the control laws of several UAV (Unmanned Aerial Vehicle) sub‐systems. The authors…
Abstract
Purpose
The purpose of this paper is to describe the tool and procedure developed in order to design the control laws of several UAV (Unmanned Aerial Vehicle) sub‐systems. The authors designed and developed the logics governing: landing gear, nose wheel steering, wheel braking, and fuel system.
Design/methodology/approach
This procedure is based on a general purpose, object‐oriented, simulation tool. The development method used is based on three‐steps. The main structure of the control laws is defined through flow charts; then the logics are ported to ANSI‐C programming language; finally the code is implemented inside the status model. The status model is a Matlab‐Simulink model, which uses an embedded Matlab‐function to model the FCC (Flight Control Computer). The core block is linked with the components, but cannot access their internal model. Interfaces between FCCs and system components in the model reflect real system ones.
Findings
The user verifies systems' reactions in real time, through the status model. Using block‐oriented approach, development of the control laws and integration of several systems is faster.
Practical implications
The tool aims to test and validate the control laws dynamically, helping specialists to find out odd logics or undesired responses, during the pre‐design.
Originality/value
The development team can test and verify the control laws in various failure scenarios. This tool allows more reliable and effective logics to be produced, which can be directly used on the system.
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Giovanni Antonio Di Meo, Sergio Chiesa, Marco Fioriti and Nicole Viola
The purpose of this paper is to perform a technical and economical analysis on the conversion of a regional turboprop platform for Airborne Early Warning and Control (AEW&C…
Abstract
Purpose
The purpose of this paper is to perform a technical and economical analysis on the conversion of a regional turboprop platform for Airborne Early Warning and Control (AEW&C) missions by supposing installation of supplementary diesel turbo‐charged engines.
Design/methodology/approach
The problem has been approached by considering all issues related to conversion to AEW&C platform. Class II methods have been used for weight and drag estimations. Flight performances have been evaluated by using standard equations of flight mechanics. Costs have been evaluated by using a model developed by the authors.
Findings
As far as performances are concerned, it is possible to increase aircraft service ceiling of about 4,400 ft by installing auxiliary diesel engines in separate wing‐nacelles. The low specific fuel consumption (SFC) of diesel engines balances the reduction of mission endurance caused by the aerodynamic drag increment (i.e. additional drag of AEW radar antenna and new nacelles). The proposed solution is shown to have the best Effectiveness‐Cost performance in comparison with other AEW&C aircraft‐systems.
Practical implications
To convert regional turboprops to AEW&C platform by employing turbocharged diesel engines could be an interesting future perspective for aerospace companies interested in creating a new AEW&C market segment.
Originality/value
The proposed solution gives the possibility to reduce operating costs in the AEW&C mission field. The issue is actual due to typical high operating costs of AEW&C missions.
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This qualitative study investigated the relationship between beauty standards and identity in the United States from the perspective of 20 self-identified millennial Black women…
Abstract
This qualitative study investigated the relationship between beauty standards and identity in the United States from the perspective of 20 self-identified millennial Black women. During semi-structured virtual interviews, participants defined Black, American, and millennial beauty standards distinctly. American beauty was associated with Eurocentrism and mainstream media representation. Interpretations of a millennial beauty standard were aligned with perceptions of the generation as tolerant and politically conscious. Black American beauty standards embraced the range of hair textures and skin tones present in the African diaspora. While participants were cognizant of the different beauty ideals present, their interaction with beauty standards was ambivalent. Interviewees found beauty knowledge accessible through social media. However, they remain confined to a restrictive beauty standard due to workplace expectations around professionalism. Participants negotiated where and when to express their intracultural beauty ideals but participated in the beauty industry through processes of learning how to care for their hair in its natural state. Even though they have autonomy and flexibility in expressing their cultural styles, personal and professional repercussions are still plausible. Future studies can expand on these findings by exploring perceptions of American beauty standards from a different generation, region, or identity.
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Claire Roederer and Marc Filser
This paper aims to contribute to the area of museum experience research, by exploring how consumers build stories to tell different experiences generated from a visit to a museum…
Abstract
Purpose
This paper aims to contribute to the area of museum experience research, by exploring how consumers build stories to tell different experiences generated from a visit to a museum and by viewing these inductive findings in the light of recent research on consumption experiences (Lanier and Rader, 2015).
Design/methodology/approach
A qualitative study is conducted. Twenty-three narratives were analysed relating a visit to ZKM museum in Karlsruhe (Germany) using narrative analysis techniques, as they are suitable to capture sensations, emotions and feelings.
Findings
ZKM museum emerges from the analysis of the narratives as a cradle for stochastic experiences (Lanier and Rader, 2015). The narratives develop several episodes that correspond to performance and liberatory experiences. A reconceptualization of the museal experience is proposed as a mesh of performance, stochastic or liberatory episodes, that capture the subject’s perspective.
Research limitations/implications
The study was limited to students who were 19-23 years of age and to one museum. Future research should include a wider age group and other museums.
Practical implications
The findings provide useful insights for curators, educators and exhibit designers staging museal experiences.
Social implications
The findings provide a better understanding of different experiences occurring in the same experiential context and their meaning from the subject’s perspective.
Originality/value
Lanier and Rader (2015) typology has not yet been tested in a museal context. The findings suggest that the same context can generate a set of various episodes (performance, liberatory, stochastic) within a given experience. From a methodological perspective, the results show that qualitative approaches are relevant to segment the museal offer based on sought experiences.
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