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The limited energy density of batteries generates the need for high-performance power sources for emerging eVTOL applications with radical operational improvement potential over traditional aircraft. This paper aims to evaluate on-design and off-design recuperated turbogenerator performances based on newly developed compression loaded ceramic turbines, the Inside-out Ceramic Turbine (ICT), in order to select the optimum engine configuration for sub-megawatt systems.

System-level thermal engine modeling is combined with electric generators and power electronics performance predictions to obtain the Pareto front between efficiency and power density for a variety of engine designs, both for recuperated and simple cycle turbines. Part load efficiency for those engines are evaluated, and the results are used for an engine selection based on a simplified eVTOL mission capability.

By operating with high turbine inlet temperature, variable output speed and adequately sized recuperator, a turbogenerator provides exceptional efficiency at both nominal power and part load operation for a turbomachine, while maintaining the high power density required for aircraft. In application with a high peak-to-cruise power ratio, such power source would provide eight times the range of battery-electric power pack and an 80% improvement over the state-of-the-art simple cycle turbogenerator.

The implementation of a recuperator would provide additional gains especially important for military and on-demand mobility applications, notably reducing the heat signature and noise of the system. The engine low-pressure ratio reduces its complexity and combined with the fuel savings, the system could significantly reduce operational cost.

Implementation of radically new ICT architecture provides the key element to make a sub-megawatt recuperated turbogenerator viable in terms of power density. The synergetic combination of a recuperator, high temperature turbine and variable speed electric generator provides drastic improvement over simple-cycle turbines, making such a system highly relevant as the power source for future eVTOL applications.

Parallel hybrid electric (HE) propulsion retrofit is a promising alternative to reduce fuel burn of aircraft operating on short regional flights. However, if the batteries are depleted at the end of the mission, the hybrid powertrain designs with downsized gas turbines (GTs) and additional electric motors might not meet the one-engine inoperative (OEI) missed approach climb performance required by the certification. Alternatively, hybrid designs using the original full-size GT can perform one engine climb without electric assistance. This paper aims to evaluate the impact of overshoot climb requirements on powertrain design and performance comparing the two design approaches.

An aircraft-level parametric mission analysis model is used to evaluate aircraft performance combined with an optimization framework including multiple constraints. An indirect approach using metamodels is used to optimize powertrain sizing and operation strategy.

Considering OEI climb requirements, no benefits were found using a design with downsized GTs. Equivalent fuel burns were found for hybrid designs that keep the original size GTs, but do not require electric energy for the OEI overshoot at the end of the mission. Then, it is recommended to size the GT to maintain the emergency climb capabilities with no electric assistance to ensure power availability regardless of remaining battery energy.

This work introduces a new perspective on parallel HE sizing with consideration for the dependency of power capability at aircraft level on the electric energy availability in case of critical mission scenarios such as overshoot climb at the end of the mission.

The purpose of this paper is to explore the professional dilemmas of historians of education in the USA.

This paper uses historiographical analysis.

While some aspects of both “prophet” and “fool” cultural archetypes fit some historians of education, neither archetype is a useful model for discussing the possible professional positions and roles of new scholars. Instead, “border-crossing” is an appropriate metaphor for new scholars in the history of education.

This manuscript addresses a topic of concern to many historians of education in multiple countries. It moves beyond material concerns of intellectuals to discuss the cultural archetypes that may be at play.

In the Netherlands, the ‘Tabaksblat Code’ (the Dutch corporate governance code of December) was a semi-private regulation instigated by the Dutch government, the stock exchange and industry associations to restore trust in the public equity markets. The aim was ‘to put the relationship between listed companies and providers of capital under the microscope’ in order to establish a new balance with a larger role for the shareholders (Tabaksblat, 2003, p. 59).

This chapter places previous incubator-incubation literature within a relevant geographic and policy context, and extracts the reasons for the wide-scale adoption of the incubator model as a new venture creation mechanism. Arguments developed highlight that in the flurry of political lobbying during the 1990s–2000s leading to the rapid expansion of incubators-incubation across the European Union (EU), policy makers, practitioners and researchers alike failed to focus on what is key to understanding incubators’ true impact — internal incubation processes. A review of incubator development and impact at the level of two EU member states, Germany and Italy, is presented. This allows for a clearer context-bound sense of the state-of-art in incubator-incubation research to emerge. In turn it becomes possible to clearly highlight the direction of further research in the area where there is a stalemate between two opposing camps — one which has produced evidence to suggest that incubators make a significant difference in reducing start-up risk, and the other, which believes incubators do not give tax payers value-for-money. Structured in this way, this chapter is able to draw attention to the essential ‘missing ingredient’ in previous research which is key to understanding the impact incubators can have. This ingredient is the dynamics of the internal process of incubation.

In this paper we present a corporate information system for untrained users to search gigabytes of unformatted data using quasi‐natural language and relevance feedback queries. The data can reside on distributed servers anywhere on a wide area network, giving the users access to personal, corporate, and published information from a single interface. Effective queries can be turned into profiles, allowing the system to automatically alert the user when new data are available. The system was tested by twenty executive users located in six cities. Our primary goal in building the system was to determine if the technology and infrastructure existed to make end‐user searching of unstructured information profitable. We found that effective search and user interface technologies for end‐users are available, but network technologies are still a limiting cost factor. As a result of the experiment, we are continuing the development of the system. This article will describe the overall system architecture, the implemented subset, and the lessons learned.

Based on recently proposed principles of total quality management (TQM), takes a system‐oriented perspective with regard to the design of performance management systems in organizations. The underlying premiss of this orientation is that methods for managing individual and group performance must be compatible with continuous improvement efforts and customer‐based TQM strategies.

Amid increasing frequency of disaster across the globe, humanitarian supply chain (HSC) has gained significant attention in recent times. This work aims to contribute towards improving the decision-making capabilities of relief organisations by offering more comprehensive understanding of the critical success factors (CSFs) concerning HSC. Hence, the current work attempts to classify CSFs as cause-and-effect factors and explore their relative importance in the stated significance.

Current work takes an explorative and deductive approach. It uses literature and experts' input to identify the CSFs for HSC and to develop a structural model for assessing these factors. Intuitionistic fuzzy DEMATEL (IF-D) is employed for modelling and analysing the cause-effect linkages among the CSFs. IF-D method is chosen as it is robust to vagueness of data and small samples.

The findings indicate that “motivated and committed employees” is the most influencing causal factor followed by “IT infrastructure”, and among effect factors, “physical network” carries the most significance followed by “anticipation capabilities.”

Relief organisations and stakeholders at various levels may put more emphasis on cause group factors with more influence on most critical effect factors to build more efficient and effective HSC to execute more impactful relief programs.

Current work explores the cause–effect relationships among the CSFs concerning HSC by implementing IF-D, which can be considered as the original contribution.

The purpose of this paper is to present a literature review and conceptual consideration of servitization in humanitarian logistics (HL) and provide a research agenda for HL scholars and insight for practitioners and by doing so will fill a gap in existing research and practice.

The paper uses a literature-based approach that extends concepts usually applied in a commercial context to the area of HL.

The paper initiates a discourse on the importance of taking into account servitization in developing and managing effective emergency relief chains. This paper argues that a broader servitization paradigm needs to be integrated for international humanitarian organisations (IHOs) to maintain a competitive advantage.

The authors investigate servitization as a management innovation in IHOs and plot a research agenda for scholars.