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High-temperature heat pumps are a key technology for enabling the complete integration of renewables into the power grid. Although these systems may come with several variants, Brayton heat pumps are gaining more and more interest because of the higher heat sink temperatures and the potential to leverage already existing components in the industry. Because these systems utilize renewable electricity to supply high-temperature heat, they are particularly suited for industry or energy storage applications, thus prompting the development of various demonstration plants to evaluate their performance and flexibility. Adapting to varying load conditions and swiftly responding to load adjustments represent crucial aspects for advancing such systems. In this context, this study delves into assessing the transient capabilities of Brayton heat pumps during thermal load management. A transient model of an emerging prototype is presented, comprising thermal and volume dynamics of the components. Furthermore, two reference scenarios are examined to assess the transient performance of the system, namely a thermal load alteration due to an abrupt change in the desired heat sink temperature and, secondly, to a sudden variation in the sink mass flow rate. Finally, two control methodologies—motor/compressor speed variation and fluid inventory control—are analyzed in the latter scenario, and a comparative analysis of their effectiveness is discussed. Results indicate that varying the compressor speed allows for a response time in the 8–20 min range for heat sink temperature regulation (first scenario). However, the regulation time is conditioned by the maximum thermal stress sustained by the heat exchangers. In the latter scenario, regulating the compressor speed shows a faster response time than the inventory control (2–5 min vs. 15 min). However, the inventory approach provides higher COPs in part-load conditions and better stability during the transient phase., Article; Export Date: 20 March 2024; Cited By: 0; Correspondence Address: M. Pettinari; Department of Energy, Systems, Territory and Construction Engineering, University of Pisa, Pisa, 56122, Italy; email: matteo.pettinari@phd.unipi.it; L. Ferrari; Department of Energy, Systems, Territory and Construction Engineering, University of Pisa, Pisa, 56122, Italy; email: lorenzo.ferrari@unipi.it

Despite increasing reliability of data generated by wearable devices, not many institutions in the healthcare sector use wearables for patient care or safety. The benefit of having accurate patient data over a certain period of time is often neglected by the fact that the medical personnel and patients do not fully accept the technological improvement. Another issue is the interoperability between the device itself and the hospital information systems, e.g. data generated may not be further processed due to lacking data standards or interfaces. In order to investigate the acceptance of stakeholders of wearable devices, a survey based on use cases was sent out to medical and administrative staff of Swiss hospitals. Finally, a technical feasibility study was conducted to investigate the technical requirements and challenges for the integration of wearable devices in the hospital IT environment.