Assessing the effectivness of policy measures with the help of qualitative modeling

The aim of a recent project of the UBA was to get a systemic and hence a better understanding of the effectiveness of measures that are meant to help achieve more sustainability in our country. Questions were raised as to why some measures had little effect and also why many measures known to be effective were not being implemented. It was also important to determine what additional measures could be taken. We began the cause and effect model by taking some predefined factors that described the overall goal of becoming a sustainable country. We then applied the KNOW WHY Method to systematically create a model that would include the crucial factors. We did this by repeatedly asking what would directly lead to more of a given factor, and what would directly hinder it, both today and in future. These are the so-called KNOW WHY questions, and we asked them for each and every factor in our model. This resulted in us being able to determine early cross connections, and through them feedback structures became apparent. The model included policy measures, social and psychological factors, as well as economical and environmental aspects. Qualitative modeling makes visible the connections that exist between so-called factors, which carry information about the direction of impact (positive or negative), the strength (weak, middle or strong) and any possible delays in terms of time (short term, medium term or long term). Taken all together, these connections can then be analyzed in so-called Insight Matrices that make it possible to compare the short, middle and long term impact of factors, and hence to see what factors are involved in creating a greater or a lesser impact – in the case of this project, this meant determining what measures promised to be more or less effective and what might hinder the success of these measures to a greater and lesser degree, both now and in the future. In our approach, the factors and connections are not mere visualizations of predefined knowledge gained by modeling experts, but the result of collaborative modeling done by experts from different fields with the aim of obtaining new insights and a deeper understanding of the complex challenge at hand. Therefore, the approach is comparable to that of grounded theory or qualitative social research where scenarios of possible developments cannot be based on empirical data from the past either. Ultimately, the model consisted of over 100 factors and had more than 1 million feedback loops. The results gained by taking this approach shed some light on why the process of change in our society on its way to becoming more sustainable is so slow. The results also explained how and why policymakers, consumers, companies and the media are dependent on each other, and made clear what obstacles the first movers among them face. The model offered an explanation for a widespread phenomenon: rationally knowing what should been done and yet. being emotionally satisfied by engaging in non-sustainable behavior. And finally, the model offered a lever, an entry into the cycle of passive, interdependent players: we need to make sustainable consumption and hence non-consumption emotionally felt through a system that scores behavior. In this short article we will provide one concrete example of how we reflected on the effectiveness of a common policy measure, i.e. the introduction of a resource tax, and how we then assessed it and determined possible impacts and constraints

Variance-Based Sensitivity Analysis of Λ\Lambda-type Quantum Memory

The storage and retrieval of photonic quantum states, quantum memory, is a key resource for a wide range of quantum applications. Here we investigate the sensitivity of $\Lambda$-type quantum memory to experimental fluctuations and drift. We use a variance-based approach, focusing on the effects of fluctuations and drift on memory efficiency. We consider shot-to-shot fluctuations of the memory parameters, and separately we consider longer timescale drift of the control field parameters. We find the parameters that a quantum memory is most sensitive to depend on the quantum memory protocol being employed, where the observed sensitivity agrees with physical interpretation of the protocols. We also present a general framework that is applicable to other figures of merit beyond memory efficiency. These results have practical ramifications for quantum memory experiments.Comment: 8 pages, 6 figures, submitted to PR

Re-melting behaviour and wear resistance of vanadium carbide precipitating Cr27.5Co14Fe22Mo22Ni11.65V2.85 high entropy alloy

High entropy alloys (HEAs) are among of the most promising new metal material groups. The achievable properties can exceed those of common alloys in different ways. Due to the mixture of five or more alloying elements, the variety of high entropy alloys is fairly huge. The presented work will focus on some first insights on the weldability and the wear behavior of vanadium carbide precipitation Cr27.5Co14Fe22Mo22Ni11.65V2.85 HEA. The weldability should always be addressed in an early stage of any alloy design to avoid welding-related problems afterwards. The cast Cr27.5Co14Fe22Mo22Ni11.65V2.85 HEA has been remelted using a TIG welding process and the resulting microstructure has been examined. The changes in the microstructure due to the remelting process showed little influence of the welding process and no welding-related problems like hot cracks have been observed. It will be shown that vanadium carbides or vanadium-rich phases precipitate after casting and remelting in a two phased HEA matrix. The hardness of the as cast alloy is 324HV0.2 and after remelting the hardness rises to 339HV0.2. The wear behavior can be considered as comparable to a Stellite 6 cobalt base alloy as determined in an ASTM G75 test. Overall, the basic HEA design is promising due to the precipitation of vanadium carbides and should be further investigated

Medium modification of pion production in low energy Au+Au collisions

There is a major mismatch between the charged pion yields in Au+Au collisions at low energies calculated by various transport models and the experimental measured values from the HADES collaboration. In this work, reasonable improvements on the equation of state, in-medium modification of cross sections, and the influence of the nuclear potential for Delta resonances will be investigated in the framework of the GiBUU transport model. As a result, we demonstrate that theoretical calculations can indeed describe the charged pion yields measured by HADES for Au+Au collisions rather well, but that a mismatch then remains between calculations and data for the yields of neutral pions extracted from dileptons within the same experiment.Comment: 14 pages, 16 figure

Wire and arc additive manufacturing of a CoCrFeMoNiV complex concentrated alloy using metal-cored wire: process, properties, and Wear Resistance

The field of complex concentrated alloys offers a very large number of variations in alloy composition. The achievable range of properties varies greatly within these variants. The experimental determination of the properties is in many cases laborious. In this work, the possibility of using metal-cored wires to produce sufficient large samples for the determination of the properties using arc-based additive manufacturing or in detail wire and arc additive manufacturing (WAAM) is to be demonstrated by giving an example. In the example, a cored wire is used for the production of a CoCrFeNiMo alloy. In addition to the process parameters used for the additive manufacturing, the mechanical properties of the alloy produced in this way are presented and related to the properties of a cast sample with a similar chemical composition. The Characterization of the resulting microstructure and wear resistance will complete this work. It will be shown that it is possible to create additively manufactured structures for a microstructure and a property determination by using metal-cored filler wires in arc-based additive manufacturing. In this case, the additively manufactured structure shows an FCC two-phased microstructure, a yield strength of 534 MPa, and a decent wear resistance

Disentangling the impact of alternative payment models and associated service delivery models on quality of chronic care: a scoping review

Payment reforms are frequently implemented alongside service delivery reforms, thus rendering it difficult to disentangle their impact. This scoping review aims to link alternative payment arrangements within their context of service delivery, to assess their impact on quality of chronic care, and to disentangle, where possible, the impact of payment reforms from changes to service delivery. A search of literature published between 2013 and 2022 resulted in 34 relevant articles across five types of payment models: capitation/global budget (n = 13), pay-for-coordination (n = 10), shared savings/shared risk (n = 6), blended capitation (n = 3), and bundled payments (n = 1). The certainty of evidence was generally low due to biases associated with voluntary participation in reforms. This scoping review finds that population-based payment reforms are better suited for collaborative, person-centred approaches of service delivery spanning settings and providers, but also highlights the need for a wider evidence base of studies disentangling the impact of financing from service delivery reforms. Limited evidence disentangling the two suggests that transforming service delivery to a team-based model of care alongside a purchasing reform shifting to blended capitation was more impactful in improving quality of chronic care, than the individual components of payment and service delivery. Further comparative studies employing causal inference methods, accounting for biases and quantifying aspects of service delivery, are needed to better disentangle the mechanisms impacting quality of care