221 research outputs found

    Deep Reinforcement Learning for Long Term Hydropower Production Scheduling

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    We explore the use of deep reinforcement learning to provide strategies for long term scheduling of hydropower production. We consider a use-case where the aim is to optimise the yearly revenue given week-by-week inflows to the reservoir and electricity prices. The challenge is to decide between immediate water release at the spot price of electricity and storing the water for later power production at an unknown price, given constraints on the system. We successfully train a soft actor-critic algorithm on a simplified scenario with historical data from the Nordic power market. The presented model is not ready to substitute traditional optimisation tools but demonstrates the complementary potential of reinforcement learning in the data-rich field of hydropower scheduling.Comment: 2020 International Conference on Smart Energy Systems and Technologies (SEST

    Hospitalized older adults' experiences of virtual reality-based group exercise therapy with cycle ergometers:An early feasibility study

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    Sedentary behavior among hospitalized older adults is a well-described challenge that can increase the risk of loss of function and mortality. Therefore, it is important to encourage physical activity (PA) during hospitalization. Exertion Games (exergames) have repeatedly been suggested as a tool to encourage and sustain motivation in rehabilitation programs. This article presents early findings from a convergent parallel mixed methods study that explored whether social presence and PA could be combined through the novel use of immersive virtual reality technology in a feasible group exercise constellation. Inpatients (n=10, 50% female, 80.3±8.2 years) were invited to participate in a bi-weekly VR group session. Most participants (62%) responded that it was a good experience to a large/great extent, which they would like to use repeatedly (76%). The technology was easy for untrained healthcare professionals and had minimal adverse events for the participants. However, a major finding illustrates that the enclosing immersiveness of the headset hindered conversation during exercise sessions. The exclusion of sight likely had a negative effect on forming relations between the participants, which conversely caused the participants to experience a lack of cohesion and relatedness with the other participants. VR-mediated group therapy may be a promising solution to existing physiotherapy practices since it may incorporate basic psychological needs. However, to optimize for social interaction, future systems will need to afford a higher degree of social presence, e.g., through avatar embodiment in a shared virtual environment, to support older adults' autonomous motivation for PA through social interaction and novel technologies

    From Burdens To Benefits: The Societal Impact Of PDL-Enriched, Efficacy-Enhanced Educators

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    Societies continue to absorb increased burdens in cost for helping citizens unable to achieve at optimal levels.  Building on past research, we project educational benefits to offset current societal burdens through enhanced educator capabilities.  Studies reviewed show participation in a high-impact professional development and learning solution resulted in improved student performance and reduced dropout rates, reduced disciplinary rates and increased rates for college-bound, along with lower teacher turnover.  Computations show that generalization of such impacts should trade societal burdens for benefits at between 3.7billionand3.7 billion and 6.9 billion within the first year.  Cumulatively within 20 years the burdens converted to benefits are projected to exceed $85 billion.  Enhanced educator capabilities will substantively reduce needs and costs for societal programs, replaced with tangible benefits to all

    Dietary pesticide chlorpyrifos-methyl affects arachidonic acid metabolism including phospholipid remodeling in Atlantic salmon (Salmo salar L.)

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    The pesticide chlorpyrifos-methyl (CLP-m) has been identified in plant ingredients intended for aquaculture feed production. To investigate systemic effects of CLP-m with emphasis on lipid metabolism, post-smolt Atlantic salmon were fed in duplicate (n = 2) either diets with no CLP-m (Control) or CLP-m at different concentrations (0.1, 1.0 or 8.0 mg kg(-1)) for a total of 67 days (Low, Medium, High). Fish in all groups almost doubled their weight during the feeding trial from 262 +/- 26 g (mean +/- SD) to 465 +/- 64 g (overall mean), with no significant effects on any growth parameters. There was a significant dose-dependent inhibition of plasma cholinesterase activity (BuChE) after 67 days. The CLP-m biotransformation metabolite, TCP was detected in liver and bile, with low levels of the parent compound in the organs. Spleen somatic index decreased significantly with increasing dietary CLP-m intake. Hematocrit (%) decreased linearly with increasing dietary exposure to CLP-m after 30 days of exposure, but this decrease was less at 67 days of exposure. A significantly reduced content of arachidonic acid (ARA 20:4n - 6), accompanied by a significantly increased content of the saturated fatty acid, palmitic acid (PA 16:0), was observed in liver phospholipids (PLs) with increasing dietary content of CLP-m. Major effects were seen on the PL classes in liver which showed a significantly decreased absolute content, possibly indicating inhibition of PL remodeling pathways or other membrane perturbation effects from CLP-m exposure. In conclusion, this study shows that the pesticide CLP-m is a relatively potent toxicant in Atlantic salmon, especially affecting liver PLs and ARA metabolism

    Transition probabilities for general birth-death processes with applications in ecology, genetics, and evolution

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    A birth-death process is a continuous-time Markov chain that counts the number of particles in a system over time. In the general process with nn current particles, a new particle is born with instantaneous rate λn\lambda_n and a particle dies with instantaneous rate μn\mu_n. Currently no robust and efficient method exists to evaluate the finite-time transition probabilities in a general birth-death process with arbitrary birth and death rates. In this paper, we first revisit the theory of continued fractions to obtain expressions for the Laplace transforms of these transition probabilities and make explicit an important derivation connecting transition probabilities and continued fractions. We then develop an efficient algorithm for computing these probabilities that analyzes the error associated with approximations in the method. We demonstrate that this error-controlled method agrees with known solutions and outperforms previous approaches to computing these probabilities. Finally, we apply our novel method to several important problems in ecology, evolution, and genetics

    Long-term feeding of Atlantic salmon with varying levels of dietary EPA þ DHA alters the mineral status but does not affect the stressresponses after mechanical delousing stress

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    Atlantic salmon were fed diets containing graded levels of EPA + DHA (1·0, 1·3, 1·6 and 3·5 % in the diet) and one diet with 1·3 % of EPA + DHA with reduced total fat content. Fish were reared in sea cages from about 275 g until harvest size (about 5 kg) and were subjected to delousing procedure (about 2·5 kg), with sampling pre-, 1 h and 24 h post-stress. Delousing stress affected plasma cortisol and hepatic mRNA expression of genes involved in oxidative stress and immune response, but with no dietary effects. Increasing EPA þ DHA levels in the diet increased the trace mineral levels in plasma and liver during mechanical delousing stress period and whole body at harvest size. The liver Se, Zn, Fe, Cu, and Mn and plasma Se levels were increased in fish fed a diet high in EPA þ DHA (3·5 %) upon delousing stress. Furthermore, increased dietary EPA þ DHA caused a significant increase in mRNA expression of hepcidin antimicrobial peptide (HAMP), which is concurrent with downregulated transferrin receptor (TFR) expression levels. High dietary EPA + DHA also significantly increased the whole-body Zn, Se, and Mn levels at harvest size fish. Additionally, the plasma and whole-body Zn status increased, respectively, during stress and at harvest size in fish fed reduced-fat diet with less EPA + DHA. As the dietary upper limits of Zn and Se are legally added to the feeds and play important roles in maintaining fish health, knowledge on how the dietary fatty acid composition and lipid level affect body stores of these minerals is crucial for the aquaculture industry

    Anbefaling på valg av standarder/rammeverk for velferdsteknologi

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    Velferdsteknologi kan gi mange, uansett alder, mulighet for å bo hjemme under trygge forhold dersom man blir syk, behøver omsorg eller bare ønsker mulighet til å bo hjemme i en sen fase i livet

    Structural Alterations from Multiple Displacement Amplification of a Human Genome Revealed by Mate-Pair Sequencing

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    Comprehensive identification of the acquired mutations that cause common cancers will require genomic analyses of large sets of tumor samples. Typically, the tissue material available from tumor specimens is limited, which creates a demand for accurate template amplification. We therefore evaluated whether phi29-mediated whole genome amplification introduces false positive structural mutations by massive mate-pair sequencing of a normal human genome before and after such amplification. Multiple displacement amplification led to a decrease in clone coverage and an increase by two orders of magnitude in the prevalence of inversions, but did not increase the prevalence of translocations. While multiple strand displacement amplification may find uses in translocation analyses, it is likely that alternative amplification strategies need to be developed to meet the demands of cancer genomics
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