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A (toy) model for cold and luke-warm strongly-coupled nuclear matter at finite baryon density and isospin chemical potential is used to study neutrino transport. The complete charged current two-point correlators are computed in the strongly-coupled medium and their impact on neutrino transport is analyzed. The full result is compared with various approximations for the current correlators and the distributions, including the degenerate approximation, the hydrodynamic approximation as well as the diffusive approximation and we comment on their successes. Further improvements are discussed., Comment: 69 pages + Appendix; 27 figures

A (toy) model for cold and luke-warm strongly-coupled nuclear matter at finite baryon density is used to study neutrino transport. The complete charged current two-point correlators are computed in the strongly-coupled medium and their impact on neutrino transport is analyzed. The full result is compared with various approximations for the current correlators and the distributions, including the degenerate approximation, the hydrodynamic approximation as well as the diffusive approximation and we comment on their successes. Further improvements are discussed., Comment: 67 pages + Appendix; 27 figures. Accepted for publication in JHEP. The treatment of isospin asymmetry was not correct in the previous version, so the isospin chemical potential is set to zero in this new version. Most of our results are qualitatively unchanged. We are planning to study the isospin asymmetric case in a future work

The single baryon solution of V-QCD is numerically computed. The spectrum of spin and isospin modes is also computed by quantizing the light fluctuations around the baryon. It is shown that there is a partial restoration of chiral symmetry at the baryon center., Comment: 46 pages + Appendix, 13 figures

The structure of the five-dimensional Tachyon-Chern-Simons action and its relevance to single-baryon states in the context of the V-QCD models for holographic QCD with backreacting flavor are analyzed. The most general form of the Tachyon-Chern-Simons 5-form, compatible with symmetries and flavor anomalies is determined. It is the sum of a non-trivial gauge-invariant 5-dimensional form and a non-invariant closed 5-form that reproduces the flavor anomalies. Single-baryon solutions of the gravity theory, arising from the DBI plus Tachyon-Chern-Simons actions are considered. The baryon is realised as a bulk axial instanton. The baryon ansatz and the field equations are derived and the boundary conditions are determined, which ensure that the solution has finite boundary energy and unit baryon charge. The boundary baryon number, which is computed from the universal (closed) part of the Tachyon-Chern-Simons action, is shown to coincide with the bulk axial instanton number., Comment: 42 pages + Appendix, 2 figures, Accepted for publication in JHEP

The single baryon solution of V-QCD is numerically computed. The spectrum of spin and isospin modes is also computed by quantizing the light fluctuations around the baryon. It is shown that there is a partial restoration of chiral symmetry at the baryon center., Comment: 46 pages + Appendix, 13 figures

The single baryon solution of V-QCD is numerically computed. The spectrum of spin and isospin modes is also computed by quantizing the light fluctuations around the baryon. It is shown that there is a partial restoration of chiral symmetry at the baryon center., Comment: 46 pages + Appendix, 13 figures

The single baryon solution of V-QCD is numerically computed. The spectrum of spin and isospin modes is also computed by quantizing the light fluctuations around the baryon. It is shown that there is a partial restoration of chiral symmetry at the baryon center., Comment: 46 pages + Appendix, 13 figures

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Introducing eight analytical approaches that are key to successful social science research, this book helps you get to grips with theory and apply it to qualitative analysis.

Contains fulltext : 228877pub.pdf (Publisher’s version ) (Closed access) Contains fulltext : 228877pos.pdf (Author’s version postprint ) (Open Access)

Contains fulltext : 228877pub.pdf (Publisher’s version ) (Closed access) Contains fulltext : 228877pos.pdf (Author’s version postprint ) (Open Access)

Climate and land-use change drive a suite of stressors that shape ecosystems and interact to yield complex ecological responses (that is, additive, antagonistic and synergistic effects). We know little about the spatial scales relevant for the outcomes of such interactions and little about effect sizes. These knowledge gaps need to be filled to underpin future land management decisions or climate mitigation interventions for protecting and restoring freshwater ecosystems. This study combines data across scales from 33 mesocosm experiments with those from 14 river basins and 22 cross-basin studies in Europe, producing 174 combinations of paired-stressor effects on a biological response variable. Generalized linear models showed that only one of the two stressors had a significant effect in 39% of the analysed cases, 28% of the paired-stressor combinations resulted in additive effects and 33% resulted in interactive (antagonistic, synergistic, opposing or reversal) effects. For lakes, the frequencies of additive and interactive effects were similar for all spatial scales addressed, while for rivers these frequencies increased with scale. Nutrient enrichment was the overriding stressor for lakes, with effects generally exceeding those of secondary stressors. For rivers, the effects of nutrient enrichment were dependent on the specific stressor combination and biological response variable. These results vindicate the traditional focus of lake restoration and management on nutrient stress, while highlighting that river management requires more bespoke management solutions.

Details of chemical heating in the CAS‐OB process are not known exactly, making a computational model valuable in process development and control. A phenomena‐based numerical model of the CAS‐OB heating stage is presented. Chemical equilibrium at reaction surfaces is assumed to be limited by mass transfer. Making use of a law of mass action based kinetic approach, reactions, and mass transfer rates are solved simultaneously. Computational fluid dynamics is used to derive heat and mass transfer coefficients, which are then used in our model, consisting of only a few computational nodes. The model includes steel melt, slag, and gas phases, bell, and ladle structures, and three reaction fronts. Radiation, conduction, and convection heat transfer are solved in the system. The model outputs temperatures and chemical composition of the system, and the results are validated with industrial data from two measurement campaigns.

The CAS-OB (composition adjustment by sealed argon bubbling - oxygen blowing) process is used in secondary steelmaking to adjust the composition and temperature of the steel melt. The steel melt can be heated by oxidizing aluminium in process which feeds aluminium particles and oxygen to the melt surface. Oxygen is in fed by a top lance, which is an important part of many metallurgical processes and is typically used to deliver oxygen to steel melt surface by supersonic blowing. Because observing and measuring the metallurgical processes is challenging due to the high temperature, numerical models predicting the processes are especially important. In this thesis, both top lances and the heat-up stage of the CAS-OB process were studied, and numerical models were constructed. CFD (computational fluid dynamics) were used to study top lances. A turbulence model was adjusted for supersonic flows with experimental data from literature. The CAS-OB process model involves chemical reactions and fluid flows. In order to keep the computation times reasonable, a full fluid flow calculation is not included in the model but is calculated in advance. Heat and mass transfer correlations are calculated with CFD, and the results are then used in the process simulation model. Chemical reactions are calculated based on the law of mass action and thermodynamics. The results were validated with industrial measurements. The CAS-OB heat-up stage model can be used in its current state in process development, and in the future for online control of the process. The CFD model for the top lance can be applied to a lance in any other process., Tiivistelmä CAS-OB-prosessia (composition adjustment by sealed argon bubbling - oxygen blowing) käytetään teräksen valmistuksessa sulan teräksen koostumuksen ja lämpötilan säätämiseen. Terässulaa voidaan tarvittaessa lämmittää syöttämällä alumiinikappaleita ja happea sulan pinnalle. Hapen syöttö tapahtuu yliäänilanssilla, jota käytetään monissa metallurgisissa prosesseissa, yleensä toimittamaan happea sulan pinnalle yliäänisellä puhalluksella. Metallurgisten prosessien havainnointi ja mittaaminen ovat haastavia korkeiden lämpötilojen vuoksi, joten numeeriset mallit ovat erityisen tärkeitä prosessien ennustamisessa. Tässä työssä on tutkittu yliäänilansseja ja CAS-OB-prosessin lämmitysvaihetta ja luotu niille numeeriset mallit. Yliäänilanssien tutkimiseen käytettiin numeerista virtauslaskentaa (CFD, computational fluid dynamics). Lanssien mallinnusta varten olemassa olevaa turbulenssimallia muokattiin paremmin yliäänivirtausta kuvaavaksi kirjallisuudesta löytyvän mittaustiedon perusteella. CAS-OB-prosessimallissa huomioidaan virtaus ja kemialliset reaktiot. Koska laskenta-ajat haluttiin pitää käytännöllisinä, virtauslaskentaa ei suoriteta mallissa, vaan se tehdään etukäteen. Aineen- ja lämmönsiirtokertoimet lasketaan CFD-laskennalla, ja tuloksia käytetään prosessimallissa. Kemialliset reaktiot lasketaan perustuen massavaikutuksen lakiin ja termodynamiikkaan. CAS-OB-mallin tulokset on validoitu terästehtaalla tehtyjen kokeiden perusteella. Mallia voidaan käyttää nykyisessä muodossaan prosessin kehityksessä ja tulevaisuudessa myös prosessin ohjauksessa. Yliäänilanssin CFD-mallia voidaan soveltaa myös muihin metallurgisiin prosesseihin.

In an earlier work, a fundamental mathematical model was proposed for side-blowing operation in the argon–oxygen decarburization (AOD) process. The purpose of this work is to present a new model, which focuses on the reactions during top-blowing in the AOD process. The model considers chemical reaction rate phenomena between the gas jet and the metal bath as well as between the gas jet and metal droplets. The rate expressions were formulated according to a law of mass action-based method, which accounts for the mass-transfer resistances in the liquid metal, gas, and slag phases. The generation rate of the metal droplets was related to the blowing number theory. This paper presents the description of the model, while validation and preliminary results are presented in the second part of this work.

In earlier work, a fundamental mathematical model was proposed for side-blowing operation in the argon oxygen decarburization (AOD) process. In the preceding part “Derivation of the Mode,” a new mathematical model was proposed for reactions during top-blowing in the AOD process. In this model it was assumed that reactions occur simultaneously at the surface of the cavity caused by the gas jet and at the surface of the metal droplets ejected from the metal bath. This paper presents validation and preliminary results with twelve industrial heats. In the studied heats, the last combined-blowing stage was altered so that oxygen was introduced from the top lance only. Four heats were conducted using an oxygen–nitrogen mixture (1:1), while eight heats were conducted with pure oxygen. Simultaneously, nitrogen or argon gas was blown via tuye’res in order to provide mixing that is comparable to regular practice. The measured carbon content varied from 0.4 to 0.5 wt pct before the studied stage to 0.1 to 0.2 wt pct after the studied stage. The results suggest that the model is capable of predicting changes in metal bath composition and temperature with a reasonably high degree of accuracy. The calculations indicate that the top slag may supply oxygen for decarburization during top-blowing. Furthermore, it is postulated that the metal droplets generated by the shear stress of top-blowing create a large mass exchange area, which plays an important role in enabling the high decarburization rates observed during top-blowing in the AOD process. The overall rate of decarburization attributable to top-blowing in the last combined-blowing stage was found to be limited by the mass transfer of dissolved carbon.

Composition Adjustment by Sealed argon bubbling – Oxygen Blowing (CAS-OB) process is a ladle treatment process that was developed for chemical heating and alloying of steel. The main stages of the process are heating, (possible) alloying and reduction of slag. The CAS-OB process aims for homogenization and control of the composition and temperature of steel. In this dissertation, a mathematical reaction model was developed for the slag reduction stage of the CAS-OB process. Slag reduction is carried out by applying vigorous bottom stirring from porous plugs at the bottom of the ladle. Due to the bottom stirring a circular steel flow is induced which disrupts top slag layer and due to shear stress at the steel-slag interface small slag droplets are detached. This induces an immense increase in the interfacial area between steel and slag which provides favourable conditions for the reduction reactions. In order to model reduction reactions, a sub-model for describing the interfacial area was needed. For this the slag droplet formation was studied using computational fluid dynamics (CFD) and based on these studies, a sub-model for droplet formation was developed. The model for the reduction stage of the CAS-OB process takes into account not only the reaction during the reduction but also the heat transfer between the phases, ladle and surroundings. The reduction stage model was validated using validation data obtained from the CAS-OB station of the SSAB Raahe steel plant in Finland. It was concluded that the model was able to predict steel and slag compositions as well as the steel temperature very well., Tiivistelmä CAS-OB -prosessi on sulametallurgiassa käytettävä senkkakäsittelyprosessi, joka on kehitetty teräksen kemialliseen lämmittäseen ja seostukseen. CAS-OB-prosessin pääprosessivaiheet ovat lämmitysvaihe, mahdollinen seostusvaihe ja kuonan pelkistysvaihe. CAS-OB -prosessilla tavoitellaan teräksen koostumuksen homogenisointiin ja lämpötilan kontrollointiin. Tässä tutkimuksessa kehitettiin matemaattinen reaktiomalli CAS-OB -prosessin kuonan pelkistysvaiheen kuvaamiseen. Kuonan pelkistys tapahtuu senkan pohjassa olevien huuhtelutiilien avulla suoritettavan voimakkaan kaasuhuuhtelun avulla. Pohjahuuhtelu aiheuttaa kiertävän teräsvirtauksen senkassa. Teräsvirtaus irrottaa teräksen päällä olevasta kuonakerroksesta pisaroita ja kuonan ja teräksen välinen reaktiopinta-ala kasvaa voimakkaasti. Tämä tarjoaa suotuisat olosuhteet pelkistysreaktiolle senkassa. Pelkistysreaktioiden mallintamiseksi tässä työssä kehitettiin CFD-simulaatioiden avulla alimalli, jonka avulla voidaan kuvata teräksen ja kuonan välisen pinta-alan suuruutta. Pelkistysvaiheen mallissa huomioidaan reaktioiden lisäksi myös systeemissä tapahtuva lämmösiirto. Pelkistysmalli validoitiin mittausdatalla, joka hankittiin SSAB Raahen terässulaton CAS-OB -asemalla järjestetyssä validointikampanjassa. Tutkimuksessa havaittiin, että malli kykenee hyvin ennustamaan teräksen ja kuonan koostumuksen sekä teräksen lämpötilan.

Lake phytoplankton are adopted world-wide as a sensitive indicator of water quality. European environmental legislation, the EU Water Framework Directive (WFD), formalises this, requiring the use of phytoplankton to assess the ecological status of lakes and coastal waters. Here we provide a rigorous assessment of a number of proposed phytoplankton metrics for assessing the ecological quality of European lakes, specifically in response to nutrient enrichment, or eutrophication, the most widespread pressure affecting lakes. To be useful indicators, metrics must have a small measurement error relative to the eutrophication signal we want them to represent among lakes of different nutrient status. An understanding of variability in metric scores among different locations around a lake, or due to sampling and analytical variability can also identify how best this measurement error is minimised. To quantify metric variability, we analyse data from a multi-scale field campaign of 32 European lakes, resolving the extent to which seven phytoplankton metrics (including chlorophyll a, the most widely used metric of lake quality) vary among lakes, among sampling locations within a lake and through sample replication and processing. We also relate these metrics to environmental variables, including total phosphorus concentration as an indicator of eutrophication. For all seven metrics, 65–96% of the variance in metric scores was among lakes, much higher than variability occurring due to sampling/sample processing. Using multi-model inference, there was strong support for relationships between among-lake variation in three metrics and differences in total phosphorus concentrations. Three of the metrics were also related to mean lake depth. Variability among locations within a lake was minimal (<4%), with sub-samples and analysts accounting for much of the within-lake metric variance. This indicates that a single sampling location is representative and suggests that sub-sample repli

Phytoplankton constitutes a diverse array of short-lived organisms which derive their nutrients from the water column of lakes. These features make this community the most direct and earliest indicator of the impacts of changing nutrient conditions on lake ecosystems. It also makes them particularly suitable for measuring the success of restoration measures following reductions in nutrient loads. This paper integrates a large volume of work on a number of measures, or metrics, developed for using phytoplankton to assess the ecological status of European lakes, as required for the Water Framework Directive. It assesses the indicator strength of these metrics, specifically in relation to representing the impacts of eutrophication. It also examines how these measures vary naturally at different locations within a lake, as well as between lakes, and how much variability is associated with different replicate samples, different months within a year and between years. On the basis of this analysis, three of the strongest metrics (chlorophyll-a, phytoplankton trophic index (PTI), and cyanobacterial biovolume) are recommended for use as robust measures for assessing the ecological quality of lakes in relation to nutrient-enrichment pressures and a minimum recommended sampling frequency is provided for these three metrics.

We describe an attempt to build a computational model for deriving dairy cows' action patterns automatically from accelerometer data.

Here we describe a wireless data measurement and transfer system that operates within a free stall barn. We report also the reliability of the system. This system was designed and built in Very Intelligent Cow Barn project in 2006-2007.

Here we describe a wireless data measurement and transfer system that operates within a free stall barn. We report also the reliability of the system. This system was designed and built in Very Intelligent Cow Barn project in 2006-2007.

We describe an attempt to build a computational model for deriving dairy cows' action patterns automatically from accelerometer data.

We describe an attempt to build a computational model for deriving dairy cows' action patterns automatically from accelerometer data.

Here we describe a wireless data measurement and transfer system that operates within a free stall barn. We report also the reliability of the system. This system was designed and built in Very Intelligent Cow Barn project in 2006-2007.

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Zoologi, Helminther, Nematoder, Acanthocephaler, IgE antistoffer, rotter

Zoologi, Helminther, Nematoder, Acanthocephaler, IgE antistoffer, rotter