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Negative carbon dioxide (CO2)-emissions are prevalent in most global emissions pathways that meet the Paris temperature targets and are a critical component for reaching net-zero emissions in Year 2050. However, economic incentives supporting commercialization and deployment of BioEnergy Carbon Capture and Storage (BECCS) are missing. This Policy and Practice Review discusses five different models for creating incentives and financing for BECCS, using Sweden as an example: (1) governmental guarantees for purchasing BECCS outcomes; (2) quota obligation on selected sectors to acquire BECCS outcomes; (3) allowing BECCS credits to compensate for hard-to-abate emissions within the EU ETS; (4) private entities for voluntary compensation; and (5) other states acting as buyers of BECCS outcomes to meet their mitigation targets under the Paris Agreement. We conclude that successful implementation of BECCS is likely to require a combination of several of the Policy Models, implemented in a sequential manner. The governmental guarantee model (Model 1) is likely to be required in the shorter term, so as to establish BECCS. Policy Models 2 and 3 may become more influential over time once BECCS has been established and accepted. Model 3 links BECCS to a large carbon-pricing regime with opportunities for cost-effectiveness and expanded financing. We conclude that Policy Models 4 and 5 are associated with high levels of uncertainty regarding the timing and volume of negative emissions that can be expected—Thus, they are unlikely to trigger BECCS implementation in the short term, although may have roles in the longer term. Based on this study, we recommend that policymakers carefully consider a policy sequencing approach that is predictable and sustainable over time, for which further analyses are required. It is not obvious how such sequencing can be arranged, as the capacities to implement the different Policy Models are vested in different organizations (national governments, EU, private firms). Furthermore, it is important that a BECCS policy is part of an integrated climate policy framework, in particular one that is in line with policies aimed at the mitigation of greenhouse gas (GHG) emissions and the creation of a circular economy. It will be important to ensure that BECCS and the associated biomass resource are not overexploited. A well-designed policy package should guarantee that BECCS is neither used to postpone the reduction of fossil fuel-based emissions nor overused in the short term as a niche business for “greenwashing” while not addressing fossil fuel emissions.

This paper provides a study of a workshop which invited composers, musicians, and sound designers to explore instruments from the history of electronic sound in Sweden. The workshop participants applied media archaeology methods towards analyzing one particular instrument from the past, the Dataton System 3000. They then applied design fiction methods towards imagining several speculative instruments of the future. Each stage of the workshop revealed very specific utopian ideas surrounding the design of sound instruments. After introducing the background and methods of the workshop, the authors present an overview and thematic analysis of the workshop's outcomes. The paper concludes with some reflections on the use of this method-in-progress for investigating the ethics and affordances of historical electronic sound instruments. It also suggests the significance of ethics and affordances for the design of contemporary instruments. QC 20210804

AbstractProbabilistic programming is an approach to reasoning under uncertainty by encoding inference problems as programs. In order to solve these inference problems, probabilistic programming languages (PPLs) employ different inference algorithms, such as sequential Monte Carlo (SMC), Markov chain Monte Carlo (MCMC), or variational methods. Existing research on such algorithms mainly concerns their implementation and efficiency, rather than the correctness of the algorithms themselves when applied in the context of expressive PPLs. To remedy this, we give a correctness proof for SMC methods in the context of an expressive PPL calculus, representative of popular PPLs such as WebPPL, Anglican, and Birch. Previous work have studied correctness of MCMC using an operational semantics, and correctness of SMC and MCMC in a denotational setting without term recursion. However, for SMC inference—one of the most commonly used algorithms in PPLs as of today—no formal correctness proof exists in an operational setting. In particular, an open question is if the resample locations in a probabilistic program affects the correctness of SMC. We solve this fundamental problem, and make four novel contributions: (i) we extend an untyped PPL lambda calculus and operational semantics to include explicit resample terms, expressing synchronization points in SMC inference; (ii) we prove, for the first time, that subject to mild restrictions, any placement of the explicit resample terms is valid for a generic form of SMC inference; (iii) as a result of (ii), our calculus benefits from classic results from the SMC literature: a law of large numbers and an unbiased estimate of the model evidence; and (iv) we formalize the bootstrap particle filter for the calculus and discuss how our results can be further extended to other SMC algorithms.

QC 20210407

This paper discusses a sensorless control technique for synchronous reluctance machines based on an alternative way to process the information obtained from the stator current oversampling. The mathematical background is presented and demonstrated through experimental validation. Implementation issues are highlighted throughout the paper. QC 20210107

We present an online API to access a number of Natural Language Processing services developed at KTH. The services work on Swedish text. They include tokenization, part-of-speech tagging, shallow parsing, compound word analysis, word inflection, lemmatization, spelling error detection and correction, grammar checking, and more. The services can be accessed in several ways, including a RESTful interface, direct socket communication, and premade Web forms. The services are open to anyone. The source code is also freely available making it possible to set up another server or run the tools locally. We have also evaluated the performance of several of the services and compared them to other available systems. Both the precision and the recall for the Granska grammar checker are higher than for both Microsoft Word and Google Docs. The evaluation also shows that the recall is greatly improved when combining all the grammar checking services in the API, compared to any one method, and combining services is made easy by the API.

QC 20221219