199 research outputs found
Nord Pool: A Power Market Without Market Power
Regulatory reform in the Nordic electricity-supply markets has resulted in a single integrated Nordic electricity market. This paper performs an econometric study of market power in the spot market of Nord Pool, the joint Nordic power exchange. I use a dynamic extension of the Bresnahan-Lau model, and weekly data for the period from 1996 through April 1999. To my knowledge, this is the first study of power markets that is not able to reject the hypothesis of perfect competition. The most likely reason for this absence of market power is the low ownership concentration in generation in the integrated Nordic electricity market.electricity markets; deregulation; market power; spot market; power exchange; electricity pool; cointegration
Övningsmetodik
Syftet med detta arbete är att undersöka frågan kring hur och varför instrumentalpedagoger ska undervisa i övning och övningsmetoder. Detta för att ge alla elever chans att utvecklas musikaliskt och instrumentalt så långt som möjligt. Arbetet behandlar områden som motivation, lärande och övning. Studien är genomförd på en kulturskola i Skåne med portföljmetod och kvalitativa intervjuer. Studien kommer fram till att det är viktigt hjälpa till med att skapa möjligheter för övning, att motivationen måste komma från individen själv och att varje individ har sina egna styrkor och svagheter, men att det ändå går att prata om en indelning av olika medvetna övningsnivåer.This study aims to answer the question about why and how music teachers should develop their pupils’ practice methods. This is to give all pupils a chance to develop as far as possible. The study discusses areas such as motivation, teaching and how to practice. The study takes place at a culture school in the south of Sweden. The method of the study is qualitative research, with interviews and portfolio as methods. The result of the study concludes that it is important to give opportunities for practice and that motivation has to come from inside. The result also shows that every individual has his or her own strengths and weaknesses, but also that there are different levels of practice methods
Conclusions from the European Roadmap on Control of Computing Systems
The use of control-based methods for resource management in real-time computing and communication systems has gained a substantial interest recently. Applications areas include performance control of web-servers, dynamic resource management in embedded systems, traffic control in communication networks, transaction management in database servers, error control in software systems, and autonomic computing. Within the European EU/IST FP6 Network of Exellence ARTIST2 on Embedded System Design a roadmap on Control of Real-Time Computing Systems has recently been completed. The focus of the roadmap is how flexibility, adaptivity, performance and robustness can be achieved in a real-time computing or communication system through the use of control theory. The item that is controlled is in most cases the allocation of computing and communication resources, e.g., the distribution or scheduling of CPU time among different competing tasks, jobs, requests, or transactions, or the communication resources in a network. Due to this, control of computing systems also goes under the name of feedback scheduling. The roadmap is divided into six research areas: control of server systems, control of CPU resources, control of communication networks, error control of software systems, feedback scheduling of control systems, and control middleware. For each area an overview is given and challenges for future research are stated. The aim of this position paper is to summarize the conclusions concerning these research challenges. In this paper, we will only cover the first four of the areas above. A preliminary version of the roadmap can be found on http://www.control.lth.se/user/karlerik/roadmap1.pd
The global build-up to intrinsic edge localized mode bursts seen in divertor full flux loops in JET
A global signature of the build-up to an intrinsic edge localized mode (ELM) is found in the temporal analytic phase of signals measured in full flux azimuthal loops in the divertor region of JET. Toroidally integrating, full flux loop signals provide a global measurement proportional to the voltage induced by changes in poloidal magnetic flux; they are electromagnetically induced by the dynamics of spatially integrated current density. We perform direct time-domain analysis of the high time-resolution full flux loop signals VLD2 and VLD3. We analyze plasmas where a steady H-mode is sustained over several seconds during which all the observed ELMs are intrinsic; there is no deliberate intent to pace the ELMing process by external means. ELM occurrence times are determined from the Be II emission at the divertor. We previously [Chapman et al., Phys. Plasmas 21, 062302 (2014); Chapman et al., in 41st EPS Conference on Plasma Physics, Europhysics Conference Abstracts (European Physical Society, 2014), Vol. 38F, ISBN 2-914771-90-8] found that the occurrence times of intrinsic ELMs correlate with specific temporal analytic phases of the VLD2 and VLD3 signals. Here, we investigate how the VLD2 and VLD3 temporal analytic phases vary with time in advance of the ELM occurrence time. We identify a build-up to the ELM in which the VLD2 and VLD3 signals progressively align to the temporal analytic phase at which ELMs preferentially occur, on a ∼2−5ms timescale. At the same time, the VLD2 and VLD3 signals become temporally phase synchronized with each other, consistent with the emergence of coherent global dynamics in the integrated current density. In a plasma that remains close to a global magnetic equilibrium, this can reflect bulk displacement or motion of the plasma. This build-up signature to an intrinsic ELM can be extracted from a time interval of data that does not extend beyond the ELM occurrence time, so that these full flux loop signals could assist in ELM prediction or mitigation
Temporal trends of molecular markers associated with artemether- lumefantrine tolerance/resistance in Bagamoyo district, Tanzania
Background: Development and spread of Plasmodium falciparum resistance to artemisinin-based combination therapy (ACT) constitutes a major threat to recent global malaria control achievements. Surveillance of molecular markers could act as an early warning system of ACT-resistance before clinical treatment failures are apparent. The aim of this study was to analyse temporal trends of established genotypes associated with artemether-lumefantrine tolerance/resistance before and after its deployment as first-line treatment for uncomplicated malaria in Tanzania 2006.
Methods: Single nucleotide polymorphisms in the P. falciparum multidrug resistance gene 1 (pfmdr1) N86Y, Y184F, D1246Y and P. falciparum chloroquine transporter gene (pfcrt) K76T were analysed from dried blood spots collected during six consecutive studies from children with uncomplicated P. falciparum malaria in Fukayosi village, Bagamoyo District, Tanzania, between 2004-2011.
Results: There was a statistically significant yearly increase of pfmdr1 N86, 184F, D1246 and pfcrt K76 between 2006-2011 from 14% to 61% (yearly OR = 1.38 [95% CI 1.25-1.52] p \u3c 0.0001), 14% to 35% (OR = 1.17 [95% CI 1.07-1.30] p = 0.001), 54% to 85% (OR = 1.21 [95% CI 1.03-1.42] p = 0.016) and 49% to 85% (OR = 1.33 [95% CI 1.17-1.51] p \u3c 0.0001), respectively. Unlike for the pfmdr1 SNP, a significant increase of pfcrt K76 was observed already between 2004-2006, from 26% to 49% (OR = 1.68 [95% CI 1.17-2.40] p = 0.005). From 2006 to 2011 the pfmdr1 NFD haplotype increased from 10% to 37% (OR = 1.25 [95% CI 1.12-1.39] p \u3c 0.0001), whereas the YYY haplotype decreased from 31% to 6% (OR = 0.73 [95% CI 0.56-0.98] p = 0.018). All 390 successfully analysed samples had one copy of the pfmdr1 gene.
Conclusion: The temporal selection of molecular markers associated with artemether-lumefantrine tolerance/resistance may represent an early warning sign of impaired future drug efficacy. This calls for stringent surveillance of artemether-lumefantrine efficacy in Tanzania and emphasizes the importance of molecular surveillance as a complement to standard in vivo trials. © 2013 Malmberg et al.; licensee BioMed Central Ltd
Introduction of large-scale biofuel production in a district heating system – an opportunity for reduction of global greenhouse gas emissions
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