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55. CIRP Conference on Manufacturing Systems, CMS, Lugano, Switzerland, 29 Jun 2022 - 1 Jul 2022; Procedia CIRP 107, 815-820 (2022). doi:10.1016/j.procir.2022.05.068 special issue: "Leading manufacturing systems transformation – proceedings of the 55th CIRP Conference on Manufacturing Systems 2022 / edited by Emanuele Carpanzano, Claudio Boër, Anna Valente", Published by Elsevier, Amsterdam [u.a.]

Summary Optimization models are a widely used tool in academia. In order to build these models, various parameters need to be specified, and often, simplifications are necessary to ensure the tractability of the models; both of which introduce uncertainty about the model results. However, a widely accepted way to quantify how these uncertainties propagate does not exist. Using the example of power system expansion modeling, we show that uncertainty propagation in optimization models can systematically be described by quantifying the sensitivity to different model parameters and model designs. We quantify the sensitivity based on a misallocation measure with clearly defined mathematical properties for two prominent examples: the cost of capital and different model resolutions. When used to disclose sensitivity information in power system studies our approach can contribute to openness and transparency in power system research. It is found that power system models are particularly sensitive to the temporal resolution of the underlying time series.

Background Chronic obstructive pulmonary disease (COPD) is the third leading cause of death globally and a common cause of hospital readmissions in the United States. While best practices exist in COPD management, incorporation of such approaches into routine clinical care remains a challenge. Objectives This evaluation applied principles from the field of dissemination and implementation (D&I) science to design a training package integrating best practice for COPD management. The D&I field promotes evidence-based implementation strategies, frameworks, and assessment approaches that can be considered by clinicians to promote adoption of best practices. Methods This prospective mixed-methods evaluation applied a D&I science model to develop, implement, and evaluate an interprofessional training program for COPD management originally piloted in 2016. The authors provide a contextual example of how a guiding D&I framework, replicating effective programs, was applied to design and implement a Web-based training program for clinicians preparing to implement the COPD service. A questionnaire and profession-specific focus group sessions were conducted to evaluate trainee confidence and enactment of critical service components. Results A total of 41 of the 50 interprofessional trainees responded to the pre- and postquestionnaire including primary care clinical pharmacists (n = 15), primary care registered nurses (n = 9), triage registered nurses (n = 12), and respiratory therapists (n = 5). Statistically significant improvements in trainee confidence and enactment were observed in 31 of the 40 total survey items (77%). Pooled focus group data provided attestation that the training enhanced practitioners’ confidence in their role within the service. Opportunities for further improvement were also identified, such as incorporating a video modeling clinic example and accompanying written materials. Conclusion This evaluation provides a case-study example of how D&I science can be used to design, implement, and evaluate a training package for trainees to spread a promising best practice. Clinicians can consider similar applications of D&I science to enhance training and spread novel services across health systems.

Density functional theory (DFT) calculations were performed on AlxCyCoFeMnNi multi-principal element alloys (MPEAs) to understand the influence of Al and C on the stacking-fault energy (SFE). C addition to CoFeMnNi resulted in increased SFE, while it decreased in Al-alloyed CoFeMnNi. For experimental verification, Al0.26CyCoFeMnNi with 0, 1.37 and 2.70 at% C were designed by computational thermodynamics, produced by additive manufacturing (AM) and characterized by tensile tests and microstructure analysis. Twinning-induced plasticity (TWIP) was enhanced with increased C, which confirmed a decreased SFE. The combination of these methods provides a promising toolset for mechanism-oriented design of MPEAs with advanced mechanical properties.

Solar photovoltaics (PV) panels in combination with batteries are often proposed as a solution to provide stable power supply in rural areas. PV generation is mostly dominated by the solar diurnal cycle and has, in some countries, already started to have influence on the daily price distribution on the electricity market. In this work, we study the performance and optimisation of rural PV-battery hybrid systems in a future renewable Polish power system. We use data on generation potentials to study PV and battery deployment. Together with a power system optimisation and dispatch model for the Polish power system, we study market values when selling at the national market for different CO2 price scenarios. We show that optimal orientations with respect to tilt/azimuth are subject to change as the PV share grows and that the benefit from batteries grows for higher shares of renewables.

We use three ensemble members of the EURO-CORDEX project and their data on surface wind speeds, solar irradiation as well as water runoff with a spatial resolution of 12 km and a temporal resolution of 3 h under representative concentration pathway 8.5 (associated with a strong climate change and a temperature increase of 2.6–4.8 °C until the end of the century) until 2100 to investigate the impact of climate change on wind, solar and hydro resources and consequently on a highly renewable and cost-optimal European power system. The weather data is transformed into power, different aspects such as capacity factors and correlation lengths are investigated and the resulting implications for the European power system are discussed. In addition, we compare a 30-node model of Europe with historical and climate change-affected data, where investments in generation, transmission and storage facilities are optimised. Differences in capacity factors among European countries are more strongly emphasized at the end of the century compared to historic data. This results in a significantly increased photovoltaic share in the cost-optimal power system. In addition, annual hydro inflow patterns of major hydro producers change considerably. System costs increase by 5% until the end of the century and the impact of climate change on these costs is of similar magnitude as differences between the ensemble members. The results show that including climate affected-weather data in power system simulations of the future has an observable effect.

Photovoltaics and wind generation are currently perceived to be a viable option for reducing the environmental impact of energy sources while simultaneously showing significant potential to reduce dependence on conventional fuels and to increase local energy security. However, the stochastic and weather-driven nature of solar and wind energy, as well as varying energy demand, makes energy systems which are based on renewables unsuitable from the perspective of power supply reliability. As a solution, they can be integrated into the power system by, for instance, energy storage in the form of pumped-storage hydroelectricity or rapidly up- and down-ramping gas power plants. This paper introduces a mathematical model for simulating and optimising the operation of a large scale solar–wind hybrid coupled with pumped-storage on a district level considering a simplified approach to incorporate grid-related cost. The model assumes spatial and temporal variability of energy generation from photovoltaics and wind turbines as well as spatial distribution of energy demand. For the purpose of including grid-related cost, we introduce a local consumption index (LCI) as a measure for decentral generation and optimise the power system with respect to different CO2 prices. We show that the introduction of the LCI facilitates the increase of renewables shares and that PV and wind are already cost-competitive at low CO2 prices.

In the process of decarbonization, the global energy mix is shifting from fossil fuels to renewables. To study decarbonization pathways, large-scale energy system models are utilized. These models require accurate data on renewable generation to develop their full potential. Using different data can lead to conflicting results and policy advice. In this work, several datasets that are commonly used to study the transition towards a highly renewable European power system are compared. Significant differences between these datasets are found, resulting in cost-differences of about 10%. These findings indicate that much more attention must be paid to the large uncertainties of the input data.

This study puts forward a new set-up for directed energy deposition (DED) with a six-beam direct diode laser head. The set-up implements three process variants, i.e. cold and hot wire as well as powder DED. The differences in the material behavior of INCONEL® alloy 718 (IN718) during additive manufacturing using the three processes is analyzed with respect to dilution, penetration into the base material, as well as solidification microstructure, second phase particles and texture. The results confirm that all three processes allow for defect-free DED of IN718, and that the hot wire process facilitates high-deposition rates with low dilution, whereas the cold wire and powder processes yield different dilution and penetration. The differences of the three process variants motivate to apply these processes interchangeably on the same part depending on the desired local microstructures, textures and thus, properties. The fundamental correlation between the processing conditions of the novel set-up used and the material behavior during DED is discussed.

To ensure reliable energy supply from power systems with high shares of variable renewable energy (VRE) sources like solar photovoltaics (PV) and wind, it is essential to include balancing options like storage and backup from dispatchable resources. In this work, we have quantified these balancing requirements for Europe and analyzed how they are influenced by different PV module configurations. We found that a favorable choice of module configuration with respect to balancing reduction is very sensitive to the shares of PV and wind. For high solar shares, highly inclined modules with a less pronounced annual course are favorable, if a storage with a capacity to cover at least 6 h of average hourly load (6 h storage) is available to compensate for the day-night cycle of PV. In a wind-dominated scenario, however, lowly inclined East/West facing modules are most suitable to reduce balancing needs. In absence of storage, a combination of highly inclined East and West facing modules reduces balancing needs as long as the solar share is high enough to distinguish between the contributions from different module configurations, although the price of such configurations in terms of additionally required installed PV capacity can be quite large.

Penetrating injuries can result in acute or subacute arterial injuries of the solid organs or extremities. Although most penetrating injuries are managed conservatively, some patients require endovascular or surgical treatment. Often, the best method for management is controversial and the level of urgency for clinical decision-making is high. Once the decision has been made to intervene, the operator must also determine the best embolization material and technique to use. Not unfrequently, these decisions are made during the course of the procedure. There are numerous embolization agents, each of which serves a very specific purpose, depending on the clinical scenario. Within this article, we will review endovascular treatment indications, contraindications, and endovascular techniques for the treatment of penetrating trauma of the solid organs or extremities.

The Vietnamese Power system is expected to expand considerably in upcoming decades. However, pathways towards higher shares of renewables ought to be investigated. In this work, we investigate a highly renewable Vietnamese power system by jointly optimising the expansion of renewable generation facilities and the transmission grid. We show that in the cost-optimal case, highest amounts of wind capacities are installed in southern Vietnam and solar photovoltaics (PV) in central Vietnam. In addition, we show that transmission has the potential to reduce levelised cost of electricity by approximately 10%.

Given an arbitrary black-box strategy for the Iterated Prisoner’s Dilemma game, it is often difficult to gauge to which extent it can be exploited by other strategies. In the presence of imperfect public monitoring and resulting observation errors, deriving a theoretical solution is even more time-consuming. However, for any strategy the reinforcement learning algorithm Q-Learning can construct a best response in the limit case. In this article I present and discuss several improvements to the Q-Learning algorithm, allowing for an easy numerical measure of the exploitability of a given strategy. Additionally, I give a detailed introduction to reinforcement learning aimed at economists.

Background: Medication overuse headache (MOH) is a prevalent and highly disabling disorder, with a strong biobehavioral component. Hence, behavioral interventions might effectuate reduction of overused medication. We assessed in a double blind manner the efficacy of a behavioral intervention during medication withdrawal therapy. Methods: In this concealed, double-blind, randomised controlled trial in MOH patients with underlying migraine we compared the effect of maximal versus minimal behavioural intervention by a headache nurse during withdrawal therapy at the outpatient Headache Clinic of the Leiden University Medical Centre. Maximal intervention consisted of an intensive contact schedule, comprising of education, motivational interviewing and value-based activity planning during the 12 weeks of acute withdrawal. Minimal intervention consisted of one short contact only. Patients were unaware of the existence of these treatment arms, as the trial was concealed in another trial investigating the added value of botulinum toxin A to withdrawal therapy. Endpoints were successful withdrawal and monthly days of acute medication use after the withdrawal period. Findings: From December 2012 to February 2016, we enrolled 179 patients (90 maximal intervention; 89 minimal intervention). At week 12, most patients achieved withdrawal in both groups (82/90 (93%) maximal intervention versus 75/89 (86%) minimal intervention, OR 2∙44 (95%CI 0∙83;7∙23), p=0∙107). At week 24, patients in the maximal intervention group had fewer acute medication days per month (mean difference -2∙23, 95%CI: -3∙76;-0∙70, p=0∙005). This difference receded over time. Interpretation: Intensive behavioral intervention by a headache nurse during withdrawal therapy for MOH patients is beneficial to reduce acute medication use during and shortly after the intervention, but extension of guidance seems warranted for a prolonged effect. The concealed study design may also be useful to investigate non-pharmacological therapies in other disorders. Trial Registration: CHARM study; www.trialregister.nl, NTR3440. Funding Statement: Supported by grants from the Netherlands Organization for Scientific Research (Terwindt VIDI 917-11-31) and the Dutch Brain Foundation (2013(1)-247). Declaration of Interests: The authors report no relevant disclosures. Ethics Approval Statement: The study was performed in accordance with the declaration of Helsinki Ethical Principles and Good Clinical Practices and was approved by the local and national ethics committees.