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Hva synes pasientene om den polikliniske behandlingen i psykisk helsevern og rusbehandling? Nasjonal bruker- og pasientundersøkelse blant voksne 2023
Get PDFRapporten presenterer resultater fra en nasjonal bruker- og pasientundersøkelse rettet mot alle voksne i poliklinisk behandling i psykisk helsevern, tverrfaglig spesialisert rusbehandling (TSB) og hos avtalespesialister i perioden februar-april 2023. Helsedirektoratets formål med denne omfattende undersøkelsen har vært å få mer kunnskap om hvordan voksne brukere og pasienter opplever behandlingstilbudene, og å bruke denne kunnskapen til å videreutvikle tilbudet og de nasjonale pasientforløpene. Det var totalt 33 457 personer som svarte på undersøkelsen – 21 346 pasienter i psykisk helsevern, 3 199 i TSB og 8 912 pasienter hos avtalespesialist. For hele dette utvalget utgjør svarprosenten 27.Hva synes pasientene om den polikliniske behandlingen i psykisk helsevern og rusbehandling? Nasjonal bruker- og pasientundersøkelse blant voksne 2023ISBN: 978-82-14-07217-4publishedVersio
Simulation study on preventing explosive mixture formation in PEM electrolysers’ water recovery tanks
Get PDFoai:sintef.brage.unit.no:11250/3166201Investigations of safety issues related to the design and operation of high-pressure proton exchange membrane (PEM) water electrolysers have until now mainly focused on the electrolyser stack. The present study focuses on the risk of explosive mixture formation in the water recovery system, which is part of the balance of plant in water electrolyser systems. After a major electrolyser company experienced an unexpected detonation in this system, we analysed their process design as a base case: a low-pressure buffer tank where anodic and cathodic water is mixed with make-up deionised water poses a safety risk because an explosive gas mixture is likely to form there, resulting in severe accidents with potential for escalation. Several retrofit options are explored using dynamic and steady-state simulation models: these options are then evaluated based on their effects on safety, general economics and operation of the plant, in addition to ease of retrofit. The results show preventing the formation of explosive gas mixtures in the water recovery system is achievable in several ways, such as avoiding recycling cathodic water altogether, stripping it of hydrogen, flushing buffer tanks with nitrogen or oxygen, rearranging the balance of plant appropriately, or changing the control algorithms of the system.publishedVersio
The impact of high-voltage circuit breaker condition on power system reliability indices
Get PDFCondition monitoring data can be used to assess the health of a power system component but is rarely used to assess the reliability of the power system they are part of. For high-voltage circuit breakers (HVCBs), the susceptibility to various failures can be assessed by examining trip coil current (TCC) measurements. HVCBs have two failure modes, failure to trip on command and tripping without a command, which are triggered by various failure mechanisms that in turn may depend on the technical condition of the HVCBs. The aim of this article is to demonstrate a methodology for quantifying the impact that the technical condition of HVCBs has on the power system reliability indices. An equivalent transmission line failure rate considering protection system failures, including failures related to HVCBs, can be calculated by computing contributions from various fault types (FTs). This article proposes a framework that can quantify the frequency of the FTs that are affected by HVCB condition. The system-level effects are then evaluated using approximate methods for power system reliability evaluation. To demonstrate the principles and benefits of this methodology, a case study is presented that incorporates HVCB condition data from the Icelandic transmission grid into an illustrative 4-bus test system; a dataset of 83 TCC measurements from 38 HVCBs from the Icelandic Transmission System Operator is used, together with an outage database of life histories of 464 HVCBs from the Icelandic transmission grid. Results indicate that the condition deterioration associated with the probability of an HVCB failing to trip on command can significantly degrade the reliability indices.The impact of high-voltage circuit breaker condition on power system reliability indicespublishedVersio
SustainableTech – A Holistic Framework for Integrated Techno-Economic and Sustainability Assessments
Get PDFA methodology is proposed to perform integrated techno-economic and life-cycle assessments of new technologies and processes. The methodology consists of a framework for decision-support considering both economic and environmental aspects in a streamlined way. This can support decision-makers to identify optimal value chains for products and activities with the aim of yielding improved economic margins and good environmental performance. Further, because of its holistic and systematic approach, the framework may provide customers with an increased awareness of trade-offs between environmental indicators and economic earnings along the value chains for different market scenarios. The developed methodology is applied to a case study involving the optimal planning for sustainable energy generation in buildings. The research expanded the original case study by incorporating additional 16 life-cycle assessment midpoint impact categories, using an updated background database, and improved techno-economic assumptions. Through this expanded analysis, alternative solutions were identified, Specifically targeting improvements in the climate change impact by exploring different permissible variances from the economic optimum.publishedVersio
Comparative validation of global and climate-specific decomposition models at high latitudes
Get PDFReliable modelling of the solar potential of urban surfaces (i.e. roofs, facades and ground) in the built environment can contribute to boost the exploitation of solar energy. Empirical and quasi-physical models are combined into model chains for this scope. Among these models, the decomposition models are used to separate the direct from the diffuse solar irradiance. Such variables are rarely measured, thus making necessary their computation. Studies in literature pointed out that Yang4 is the bestperforming decomposition model globally. However, in geographically limited applications, quasi-universal decomposition models like Yang4 and Engerer4 can be outperformed by local models (i.e. models parametrized with climate-specific data) such as Skartveit3 and Starke3. This makes necessary to perform local validation studies to verify the findings from worldwide validation studies. In this study, the four bestperforming decomposition models are implemented in Python and experimentally validated against 1-min solar irradiance data (i.e. direct and diffuse irradiance) of Trondheim (Lat. 63 26#N, Norway). More than 1-year long data are considered. The study confirms that the Yang4 model performed the best for high-latitude applications, but Starke3 can achieve a level of performance close to Yang4.publishedVersio
Grand challenges of wind energy science - Meeting the needs and services of the power system
Get PDFThe share of wind power in power systems is increasing dramatically, and this is happening in parallel with increased penetration of solar photovoltaics, storage, other inverter-based technologies, and electrification of other sectors. Recognising the fundamental objective of power systems, maintaining supply–demand balance reliably at the lowest cost, and integrating all these technologies are significant research challenges that are driving radical changes to planning and operations of power systems globally. In this changing environment, wind power can maximise its long-term value to the power system by balancing the needs it imposes on the power system with its contribution to addressing these needs with services. A needs and services paradigm is adopted here to highlight these research challenges, which should also be guided by a balanced approach, concentrating on its advantages over competitors. The research challenges within the wind technology itself are many and varied, with control and coordination internally being a focal point in parallel with a strong recommendation for a holistic approach targeted at where wind has an advantage over its competitors and in coordination with research into other technologies such as storage, power electronics, and power systems.publishedVersio
A Platform for Development and Testing of WAMPAC Applications based on Kafka Streaming
Get PDFIn this paper a platform for developing and testing Wide Area Monitoring, Protection and Control (WAMPAC) applications is presented. The fundamental idea is that individual applications operate as microservices. Each application access and process data (e.g. data from Phasor Measurement Units) and produces results which can be further elaborated by other microservices, or directly presented to the operators. Streaming of data between microservices is handled by a Kafka streaming server which handles the complete information flow.The platform has been tested both on data streams from a lightweight real-time simulator (with hundreds of measurement channels), and on PMU streams generated from recorded data from the Nordic system (with thousands of measurement channels). The platform is characterized by low need of computational resources and easy installation (only requiring basic Python programming skills). Experience from this work indicates that the chosen approach is suitable for streamlining the process of development and testing of WAMPAC applications, with the aim of raising the technology readiness level of already existing applications in the literature or for future applications.A Platform for Development and Testing of WAMPAC Applications based on Kafka StreamingacceptedVersio
AI-driven sustainable cities: A Nordic-inspired requirement framework
Get PDFThis paper examines the integration of AI and data technologies into sustainable urban development, emphasizing Norway's unique cultural and environmental context. It first explores how concepts like trust and sustainability inform urban planning and operations. Then, the study assesses AI's potential to enhance urban development, and, through case studies, it identifies challenges and opportunities in adopting these technologies. Finally, it proposes a Nordic requirement framework for AI and data integration, promoting sustainability aligned with Norway's values and adaptable for broader European contexts.publishedVersio
Relaxed Nonlinear Vector Fitting for Calculation of Rational Approximation of Systems Defined by Input/Output Responses in the Frequency Domain
Get PDFThe so-called non-linear vector fitting (NL-VF) technique was recently introduced as a new method for rational function approximation in the frequency domain (FD). While the classical vector fitting (VF) fits a rational function to a given frequency response, NL-VF calculates the rational function approximation based on a set of input/output responses that characterize the system. The frequency responses can come from time domain (TD) responses that are transformed to the FD using the Numerical Laplace Transform (NLT), or it can be the set of frequency responses that result when characterizing non-linear systems in the FD, at a given operating point. This paper extends NL-VF to its relaxed version by replacing the scaling function used for pole relocation by a more relaxed constraint, following a similar approach as in the relaxed VF method. This paper shows that the relaxed NL-VF exhibits an improvement in both convergence and accuracy, as compared to its original formulation. The advantages are demonstrated for three examples of rational function approximation, 1) FD transfer function of a transmission line propagation function, 2) FD input/output variables of a system which includes a photovoltaic generator and a nonlinear reactor, and 3) TD measurements of an automatic voltage regulator response.Relaxed Nonlinear Vector Fitting for Calculation of Rational Approximation of Systems Defined by Input/Output Responses in the Frequency DomainacceptedVersio
Metatranscriptome analysis reveals the putative venom toxin repertoire of the biofouling hydroid Ectopleura larynx
Get PDFCnidarians thriving in biofouling communities on aquaculture net pens represent a significant health risk for farmed finfish due to their stinging cells. The toxins coming into contact with the fish, during net cleaning, can adversely affect their behavior, welfare, and survival, with a particularly serious health risk for the gills, causing direct tissue damage such as formation of thrombi and increasing risks of secondary infections. The hydroid Ectopleura larynx is one of the most common fouling organisms in Northern Europe. However, despite its significant economic, environmental, and operational impact on finfish aquaculture, biological information on this species is scarce and its venom composition has never been investigated. In this study, we generated a whole transcriptome of E. larynx, and identified its putative expressed venom toxin proteins (predicted toxin proteins, not functionally characterized) based on in silico transcriptome annotation mining and protein sequence analysis. The results uncovered a broad and diverse repertoire of putative toxin proteins for this hydroid species. Its toxic arsenal appears to include a wide and complex selection of toxin proteins, covering a large panel of potential biological functions that play important roles in envenomation. The putative toxins identified in this species, such as neurotoxins, GTPase toxins, metalloprotease toxins, ion channel impairing toxins, hemorrhagic toxins, serine protease toxins, phospholipase toxins, pore-forming toxins, and multifunction toxins may cause various major deleterious effects in prey, predators, and competitors. These results provide valuable new insights into the venom composition of cnidarians, and venomous marine organisms in general, and offer new opportunities for further research into novel and valuable bioactive molecules for medicine, agronomics and biotechnology.publishedVersio