| 1. |
- de Jeu, Marcel, et al.
(författare)
-
Algebraic curves for commuting elements in the $q$-deformed Heisenberg algebra
- 2009
-
Ingår i: Journal of Algebra. - : Elsevier BV. - 0021-8693 .- 1090-266X. ; 321:4, s. 1239-1255
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we extend the eliminant construction of Burchnall and Chaundy for commuting differential operators in the Heisenberg algebra to the q-deformed Heisenberg algebra and show that it again provides annihilating curves for commuting elements, provided q satisfies a natural condition. As a side result we obtain estimates on the dimensions of the eigenspaces of elements of this algebra in its faithful module of Laurent series.
|
|
| 2. |
- Silvestrov, Sergei, 1970-, et al.
(författare)
-
Algebraic dependence of commuting elements in algebras
- 2009
-
Ingår i: Generalized Lie theory in mathematics, physics and beyond. - Berlin, Heidelberg : Springer Berlin/Heidelberg. - 9783540853312 - 9783540853329 ; , s. 265-280
-
Bokkapitel (refereegranskat)abstract
- The aim of this paper to draw attention to several aspects of the algebraic dependence in algebras. The article starts with discussions of the algebraic dependence problem in commutative algebras. Then the Burchnall—Chaundy construction for proving algebraic dependence and obtaining the corresponding algebraic curves for commuting differential operators in the Heisenberg algebra is reviewed. Next some old and new results on algebraic dependence of commuting q-difference operators and elements in q-deformed Heisenberg algebras are reviewed. The main ideas and essence of two proofs of this are reviewed and compared. One is the algorithmic dimension growth existence proof. The other is the recent proof extending the Burchnall–Chaundy approach from differential operators and the Heisenberg algebra to the q-deformed Heisenberg algebra, showing that the Burchnall—Chaundy eliminant construction indeed provides annihilating curves for commuting elements in the q-deformed Heisenberg algebras for q not a root of unity.
|
|
| 3. |
- Ahlberg, Simon, et al.
(författare)
-
An information fusion demonstrator for tactical intelligence processing in network-based defense
- 2007
-
Ingår i: Information Fusion. - : Elsevier BV. - 1566-2535 .- 1872-6305. ; 8:1, s. 84-107
-
Tidskriftsartikel (refereegranskat)abstract
- The Swedish Defence Research Agency (FOI) has developed a concept demonstrator called the Information Fusion Demonstrator 2003 (IFD03) for demonstrating information fusion methodology suitable for a future Network Based Defense (NBD) C4ISR system. The focus of the demonstrator is on real-time tactical intelligence processing at the division level in a ground warfare scenario. The demonstrator integrates novel force aggregation, particle filtering, and sensor allocation methods to create, dynamically update, and maintain components of a tactical situation picture. This is achieved by fusing physically modelled and numerically simulated sensor reports from several different sensor types with realistic a priori information sampled from both a high-resolution terrain model and an enemy organizational and behavioral model. This represents a key step toward the goal of creating in real time a dynamic, high fidelity representation of a moving battalion-sized organization, based on sensor data as well as a priori intelligence and terrain information, employing fusion, tracking, aggregation, and resource allocation methods all built on well-founded theories of uncertainty. The motives behind this project, the fusion methods developed for the system, as well as its scenario model and simulator architecture are described. The main services of the demonstrator are discussed and early experience from using the system is shared.
|
|
| 4. |
- Anderbrant, Olle, et al.
(författare)
-
Odour signals for detection and control of indoor pyralid moths
- 2009
-
Ingår i: IOBC/WPRS Bulletin. - 1027-3115. ; 41, s. 69-74
-
Tidskriftsartikel (refereegranskat)abstract
- Three pyralid moths, the Mediterranean flour moth (Ephestia kuehniella), the almond moth (Ephestia cautella) and the Indian meal moth (Plodia interpunctella), infest food products all over the world and cause severe problems in factories, shops and households. For health and environmentalreasons chemical control becomes more and more restricted. We here present some promising results offering efficient detection and control of these species based on semiochemicals, and line up a number of remaining questions to be answered in order to improve the reliability and competitiveness of the methods used. For P. interpunctella and E. cautella we found that more complex pheromone blends were superior to the commercially available one-component blend in attracting males, andshould be used if increased sensitivity is desired. The almond moth, males as well as females, can be trapped in buckets with tap water, which will give an estimate of the population level without use of pheromone traps. All three species show positive response to odours identified from chocolate, and this could possibly be developed further and used to determine relative population densities. For population suppression the pheromone-mediated mating disruption technique was employed inlocalities with infestations of all three species. Based on several indirect methods to estimate the population densities we conclude that this technique has a large potential for controlling all three mothspecies.
|
|
| 5. |
|
|
| 6. |
- Besnard, Céline, et al.
(författare)
-
Diquino[4,3-b;3 ',4 '-e][1,4]thiaselenine
- 2006
-
Ingår i: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; 62:8, s. 3203-3205
-
Tidskriftsartikel (refereegranskat)abstract
- The title compound, C18H10N2SSe, is a pentacyclic ring system folded along the S center dot center dot center dot Se vector. The central thiaselenine ring adopts a boat conformation and the two halves of the molecule are related by a crystallographic mirror plane.
|
|
| 7. |
- Brorström-Lundén, Eva, et al.
(författare)
-
Measurements of Sucralose in the Swedish Screening program 2007. PART II; Sucralose in Biota samples and regional STP samples
- 2008
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- IVL has performed a 'screening study' of sucralose on commission from the Swedish EPA, reported in two consecutive parts. Sucralose is a chlorine containing derivative of sucrose, manufactured by selectively substituting three hydroxyls with chlorine. The substance is used as a sweetener in food products; on a weight basis it tastes ca. 600 times sweeter than the parent compound. The objectives of the study were to determine the concentrations of sucralose in media in the Swedish environment such as biota, wastewater effluents and to highlight important transport pathways. In total 84 samples were analysed. This report constitutes part 2 of the study.
|
|
| 8. |
- Dencker, Magnus, et al.
(författare)
-
Daily physical activity and its relation to aerobic fitness in children aged 8-11 years.
- 2006
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6327 .- 1439-6319. ; 96:5, s. 587-592
-
Tidskriftsartikel (refereegranskat)abstract
- A positive relationship between daily physical activity and aerobic fitness exists in adults. Studies in children have given conflicting results, possibly because of differences in methods used to assess daily physical activity and fitness. No study regarding daily physical activity and fitness in children has been published, where fitness has been assessed by direct measurement of maximum oxygen uptake and related to daily physical activity intensities by accelerometers. We examined 248 children (140 boys and 108 girls), aged 7.9-11.1 years. Maximum workload and maximal oxygen uptake (VO2PEAK) by indirect calorimetry were measured during a maximum bicycle ergometer exercise test. Exercise capacity was adjusted for body mass and (body mass)(2/3). Daily physical activity was evaluated by accelerometers, worn around the waist for 4 days. Mean accelerometer counts and time spent in vigorous physical activity were calculated. VO2PEAK was correlated with mean accelerometer counts (r=0.23 for boys and r=0.23 for girls, both P < 0.05), but somewhat better with time spent in vigorous activity (r=0.32 for boys, r=0.30 for girls, both P < 0.05). All results remained virtually the same regardless of the method used to adjust for differences in body size.
|
|
| 9. |
- Heath, Christian, et al.
(författare)
-
Video and qualitative research : analysing medical practice and interaction
- 2007
-
Ingår i: Medical education. - : Blackwell Publishing. - 1365-2923. ; 41:1, s. 109-116
-
Tidskriftsartikel (refereegranskat)abstract
- There has been a longstanding recognition that video provides an important resource within medical education particularly, perhaps, for training in primary health care. As a resource for research, and more specifically within qualitative social science studies of medical practice, video has proved less pervasive despite its obvious advantages. In this paper, we sketch an approach for using video to inform the analysis of medical practice and the ways in which health care is accomplished through social interaction and collaboration. Drawing on our own research we discuss two brief examples; one the use of computing technology in primary health care and secondly informal instruction during surgical operations. The examples illustrate the multimodal character of medical work, how activities are accomplished through the interplay of talk, the visual and the use of material artefacts. They also illustrate the ways in which video provides access to the complex forms of social interaction and collaboration that underpin health care. We reflect upon the research opportunities afforded by video and the ways in which video based studies of interaction can contribute to the practice and practicalities of medicine.
|
|
| 10. |
- Herrmann, Inga, et al.
(författare)
-
Hydraulic conductivity of fly ash : sewage sludge mixes for use in landfill cover liners
- 2009
-
Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 43:14, s. 3541-3547
-
Tidskriftsartikel (refereegranskat)abstract
- Secondary materials could help meeting the increasing demand of landfill cover liner materials. In this study, the effect of compaction energy, water content, ash ratio, freezing, drying and biological activity on the hydraulic conductivity of two fly ash - sewage sludge mixes was investigated using a 27-1 fractional factorial design. The aim was to identify the factors that influence hydraulic conductivity, to quantify their effects and to assess how a sufficiently low hydraulic conductivity can be achieved. The factors compaction energy and drying, as well as the factor interactions material×ash ratio and ash ratio×compaction energy affected hydraulic conductivity significantly (α = 0.05). Freezing on 5 freeze-thaw cycles did not affect hydraulic conductivity. Water content affected hydraulic conductivity only initially. The hydraulic conductivity data were modelled using multiple linear regression. The derived models were reliable as indicated by R2adjusted values between 0.75 and 0.86. Independent on the ash ratio and the material, hydraulic conductivity was predicted to be between 1.7 × 10-11 m s-1 and 8.9 × 10-10 m s-1 if the compaction energy was 2.4 J cm-3, the ash ratio between 20 and 75 % and drying did not occur. Thus, the investigated materials met the limit value for non-hazardous waste landfills of 10-9 m s-1.
|
|
