4,295 research outputs found

    Cut-elimination for the mu-calculus with one variable

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    We establish syntactic cut-elimination for the one-variable fragment of the modal mu-calculus. Our method is based on a recent cut-elimination technique by Mints that makes use of Buchholz' Omega-rule.Comment: In Proceedings FICS 2012, arXiv:1202.317

    Potential of distributed wood-based biopower systems serving basic electricity needs in rural Uganda

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    Thomas Buchholz, Izael Pereira Da Silva - Energy for Sustainable DevelopmentCurrent efforts to improve electricity services in Uganda evolve around satisfying growing urban demand as well as stabilizing and boosting a low electricity supply. Although virtually non-existent, rural electrification is receiving very little attention. This paper investigates the potential of wood-based biopower fueled from coppicing shrubs on its feasibility to provide affordable basic electricity services to rural Ugandan households. Gasification was the specific technology we assessed. In the calculations, a worst case scenario was chosen for wood-based biopower to compete with alternative sources of electricity: Cost and land use estimates assumed a rather high household consumption (30 kWh/month), a low household size (8 persons), a low area productivity (3 oven-dried tons per ha per year), a low electrical conversion efficiency (15%) and a high demand competing for fertile land with the biopower system. Cost estimates considered a high biomass price (18.5 US/odt),alowcapacityfactorforthebiopowersystemof0.5(thereforerequiringinstallationofalargerunit)andhighcapitalcostsof2300US/odt), a low capacity factor for the biopower system of 0.5 (therefore requiring installation of a larger unit) and high capital costs of 2300 US per kW installed. Additional pressure on fertile land would be negligible. Such biopower systems can outcompete other sources of electricity from a micro and macro-economic standpoint when looking at the local scale. Results indicate that biopower can deliver better and more energy services at 47 US/yrandhouseholdor0.11US/yr and household or 0.11 US/kWh which is below current average costs for e.g. off-grid lighting in rural Ugandan households. Additionally, only this biopower option offers the ability to households, sell wood to the biopower system and contribute at least four times as much to the local economy than the other electricity options used as terms of comparison. Further research has to focus on developing business plans and loan schemes for such biopower options including sustainable fuelwood supply chains based on coppicing shrubs which have the ability to contribute to agricultural site improvements. The approach outlined in this paper can further serve as a general framework to compare different options of electricity production across technologies and fuel sources especially for rural development purposes incorporating a multitude of aspects.Current efforts to improve electricity services in Uganda evolve around satisfying growing urban demand as well as stabilizing and boosting a low electricity supply. Although virtually non-existent, rural electrification is receiving very little attention. This paper investigates the potential of wood-based biopower fueled from coppicing shrubs on its feasibility to provide affordable basic electricity services to rural Ugandan households. Gasification was the specific technology we assessed. In the calculations, a worst case scenario was chosen for wood-based biopower to compete with alternative sources of electricity: Cost and land use estimates assumed a rather high household consumption (30 kWh/month), a low household size (8 persons), a low area productivity (3 oven-dried tons per ha per year), a low electrical conversion efficiency (15%) and a high demand competing for fertile land with the biopower system. Cost estimates considered a high biomass price (18.5 US/odt),alowcapacityfactorforthebiopowersystemof0.5(thereforerequiringinstallationofalargerunit)andhighcapitalcostsof2300US/odt), a low capacity factor for the biopower system of 0.5 (therefore requiring installation of a larger unit) and high capital costs of 2300 US per kW installed. Additional pressure on fertile land would be negligible. Such biopower systems can outcompete other sources of electricity from a micro and macro-economic standpoint when looking at the local scale. Results indicate that biopower can deliver better and more energy services at 47 US/yrandhouseholdor0.11US/yr and household or 0.11 US/kWh which is below current average costs for e.g. off-grid lighting in rural Ugandan households. Additionally, only this biopower option offers the ability to households, sell wood to the biopower system and contribute at least four times as much to the local economy than the other electricity options used as terms of comparison. Further research has to focus on developing business plans and loan schemes for such biopower options including sustainable fuelwood supply chains based on coppicing shrubs which have the ability to contribute to agricultural site improvements. The approach outlined in this paper can further serve as a general framework to compare different options of electricity production across technologies and fuel sources especially for rural development purposes incorporating a multitude of aspects

    Classification of subsystems for graded-local nets with trivial superselection structure

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    We classify Haag-dual Poincar\'e covariant subsystems \B\subset \F of a graded-local net \F on 4D Minkowski spacetime which satisfies standard assumptions and has trivial superselection structure. The result applies to the canonical field net \F_\A of a net \A of local observables satisfying natural assumptions. As a consequence, provided that it has no nontrivial internal symmetries, such an observable net \A is generated by (the abstract versions of) the local energy-momentum tensor density and the observable local gauge currents which appear in the algebraic formulation of the quantum Noether theorem. Moreover, for a net \A of local observables as above, we also classify the Poincar\'e covariant local extensions \B \supset \A which preserve the dynamics.Comment: 38 pages, LaTe

    Joint versus separate inpatient rehabilitation treatment for patients with alcohol use disorder or drug use disorder : an observational study

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    Background: In many national treatment systems, patients with alcohol use disorders (AUD) and those with drug use disorders (DUD) are treated separately, while other systems provide joint treatment for both kinds of substance use disorders (SUDs). Regarding long-term rehabilitation treatment of DUD and AUD patients, there is however a lack of empirical studies on the comparison between a separate versus joint treatment modality. Methods: Data were gathered from 2 rehabilitation units located in small towns from the same German region. One unit provided treatment to a mixed group of AUD and DUD patients, while the other unit treated the 2 groups separately. Staffing, funding, and treatment programs were otherwise similar between facilities. Data were gathered from standardized routine documentation and standardized interviews. In order to understand correlates of premature treatment termination, a logistic regression analysis was performed, with treatment modality and type of SUD as main predictors, and a range of patient characteristics as covariates. Results: Patients (N=319) were diagnosed with AUD (48%), DUD (34%), or AUD plus DUD (18%). Patients in joint treatment showed a higher prevalence of lapses during treatment than those in separate treatment (26% versus 12%; p=0.009), but there was no significant difference in the prevalence of premature terminations (38% versus 44%, p=0.26). Treatment modality and interaction between modality and type of SUD was not significantly associated with premature termination. Joint treatment completers showed higher satisfaction with treatment than separate treatment completers ( p<0.001). Conclusion: We found no evidence here for a difference between treatment modalities in terms of premature termination rate. Satisfaction level was higher in those who completed joint treatment compared to separate treatment.Peer reviewe

    Low-latency Cloud-based Volumetric Video Streaming Using Head Motion Prediction

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    Volumetric video is an emerging key technology for immersive representation of 3D spaces and objects. Rendering volumetric video requires lots of computational power which is challenging especially for mobile devices. To mitigate this, we developed a streaming system that renders a 2D view from the volumetric video at a cloud server and streams a 2D video stream to the client. However, such network-based processing increases the motion-to-photon (M2P) latency due to the additional network and processing delays. In order to compensate the added latency, prediction of the future user pose is necessary. We developed a head motion prediction model and investigated its potential to reduce the M2P latency for different look-ahead times. Our results show that the presented model reduces the rendering errors caused by the M2P latency compared to a baseline system in which no prediction is performed.Comment: 7 pages, 4 figure

    SHPbench – a smart hybrid prototyping based environment for early testing, verification and (user based) validation of advanced driver assistant systems of cars

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    Statistical analysis show that more than 90 percent of all car accidents result from human mistakes. Advanced Driver Assistant Systems (ADAS) are intended to support and assist the car driver, and therefore contribute significantly to the reduction of accidents. ADAS become more and more complex and demanding regarding hard- and software fulfilling the requirements applied onto assistant systems nowadays and in the future. They have to be considered as multi-functional multi-domain mechatronic systems. Smart Hybrid Prototyping (SHP) is a by now proven approach for handling ADAS’ demands during and to the development process, specifically for early integrated component and system testing, its verification and validation with the focus on the interaction with the driver can only be reasonably and economically met by utilizing the SHP technology. For those mentioned purposes the SHPbench, an integrated development and validation environment, has been recently developed. The SHPbench's architecture and specification is presented and evaluated by applying a representative use case of an ADAS development process. This paper documents the use case setup, process steps and test results

    Extrinsic Infrastructure Calibration Using the Hand-Eye Robot-World Formulation

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    We propose a certifiably globally optimal approach for solving the hand-eye robot-world problem supporting multiple sensors and targets at once. Further, we leverage this formulation for estimating a geo-referenced calibration of infrastructure sensors. Since vehicle motion recorded by infrastructure sensors is mostly planar, obtaining a unique solution for the respective hand-eye robot-world problem is unfeasible without incorporating additional knowledge. Hence, we extend our proposed method to include a-priori knowledge, i.e., the translation norm of calibration targets, to yield a unique solution. Our approach achieves state-of-the-art results on simulated and real-world data. Especially on real-world intersection data, our approach utilizing the translation norm is the only method providing accurate results.Comment: Accepted at 2023 IEEE Intelligent Vehicles Symposiu
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