Full discretisation of semi-linear stochastic wave equations driven by multiplicative noise

A fully discrete approximation of the semi-linear stochastic wave equation driven by multiplicative noise is presented. A standard linear finite element approximation is used in space and a stochastic trigonometric method for the temporal approximation. This explicit time integrator allows for mean-square error bounds independent of the space discretisation and thus do not suffer from a step size restriction as in the often used St\"ormer-Verlet-leap-frog scheme. Furthermore, it satisfies an almost trace formula (i.e., a linear drift of the expected value of the energy of the problem). Numerical experiments are presented and confirm the theoretical results

A comparative case study of non technical barriers for combined heat and power and district heating diffusion in Sweden and the United Kingdom

The subject of this thesis is the non technical drivers and barriers which are observed for the two energy saving technologies Combined Heat and Power (CHP) and District Heating (DH) in the United Kingdom and in Sweden. Due to lack of specific theory applicable to the specific technologies a general theory based in market failure, institutional and technologic diffusion theory has been used for understanding and analysing the market phenomena and for making policy recommendations. The thesis has been written as a comparative case study comparing two individual market case studies of the UK and Swedish CHP and DH markets. Qualitative data has been collected through a series of interviews which have been analysed using the coding and clustering method developed in Miles and Huberman (1994) The results from the research show that the formal as well as informal institutional environment on the respective market is of significant importance for the uptake of CHP and DH presently and historically. The current and past policy as well as the information available on a market is important to avoid market failures for CHP and DH. This thesis recommends the use of more mandatory regulations, institutional innovation and stronger financial incentives in the United Kingdom to increase the uptake of CHP and DH

Canopy reflectance and image analysis to determine plant biomass in field experiments

I traditionella fältförsök har den vanligaste metoden för att bestämma biomassa och kvävemängd varit att klippa prover i den växande grödan. Denna bestämning blir tidskrävande och på så sätt dyr, vilket gör den svår att utföra flera gånger under en växtsäsong. Efterfrågan har därför vuxit efter en tillförlitlig metod som är effektiv och som därmed gör det möjligt att mäta med tätare intervaller, men som ändå inte är oskäligt dyr. Detta examensarbete har inriktat sig till att undersöka om grödors reflektans som mäts med en hyperspektral sensor kan vara användbar för att bestämma biomassa, kvävemängd och kvävehalt och på så vis vara användbar i försöksverksamheten. Dessutom har metoden bildanalys jämförts med sensormätningar. Försöket startade 2010-04-16 och pågick med löpande mätningar till 2010-06-30 i sju jordbearbetningsförsök. För att mäta reflektansen har Yara’s handburna sensor använts, vilken mäter grödreflektansen mellan 400 och 1000 nm. Fyra mätningar gjordes i varje ruta vid flera tillfällen under våren och försommaren. Fram till och med att grödan slöt sig fotograferades även varje ruta vid samma tillfälle som reflektansmätningarna. Detta utfördes genom att fyra fotografier togs i varje försöksruta med en digitalkamera på stativ, vilket gav en yta på 0,22 m2/foto. Bilderna analyserades sedan digitalt för att ge den andel som grödan täckte av marken. Vid varje tillfälle bestämdes även biomassan genom att klippa en kvadratmeter och sedan väga denna efter torkning. För att korrelera reflektansen till biomassa, kvävemängd och kvävehalt användes följande vegetationsindex; NDVI, OSAVI, GNDVI, NIR/Red, NIR/Green, REIP, TrVI, TCARI och TC/OS. Dessutom testades parametrarnas samband med reflektansen för våglängderna, 780 nm, 850 nm och 780-670 nm. Resultaten visade på goda korrelationer mellan biomassan och flera av indexen. Även kvävemängden visade god korrelation till indexen. Mellan kvävehalten och indexen var det däremot svårt att hitta någon hög korrelation. De fyra indexen som generellt sett gav högst korrelation var NDVI, NIR/Green, 780 nm och 780-670 nm. NIR/Green var det index som visade allra högst korrelation till parametrarna och kom därför att användas vid bestämning av ledskillnader i försöken. Bildanalysen gav god korrelation till både NDVI och NIR/Green. Problem som kunde ses med biomassabestämning genom grödreflektans var att skörderester kunde ge upphov till en högre reflektans vid tidiga mätningar. En annan brist var att det var svårt att finna en god korrelation med kvävehalten. För övrigt fungerade metoden mycket tillfredställande och kan definitivt vara ett hjälpmedel för biomassabestämning, men kanske framförallt bidra med en förklaring till utvecklingen mellan leden i fältförsök.In traditional Swedish field experiments in crop production, plant development during vegetative stages is usually determined by visual assessment or by cutting the crop. Measurements of canopy reflectance as well as digital image analysis offer non-destructive and quick methods which can be used to determine crop biomass and area covered by vegetation. The objective of the work presented here was to compare measurements of canopy reflectance with measurements of aboveground plant biomass, content of nitrogen in the crop and image analysis of leaf area coverage. Measurements were made between 16 April and 30 June in 2010 in totally 7 field experiments with soil tillage. A handheld Yara N-sensor equipment was used which measured reflectance in the interval 400-1000 nm. Four measurements were made in each plot of the experiments at several occasions during the spring and early summer. Until canopy closure, the crop was photographed at the same occasions as the reflectance measurements. Four pictures per plot were taken with a camera mounted on a tripod, each picture covered an area of approximately 0.22 m2. The pictures were digitally analyzed to calculate the area covered by green leaves. At each measuring occasion, the aboveground biomass was determined. This was normally done in one of the treatments by cutting the crop in 1 m2, followed by drying and weighing. The vegetation indices that were used to correlate the parameters to the reflectance was: NDVI, OSAVI, GNDVI, NIR/Red, NIR/Green, REIP, TrVI, TCARI and TC/OS. Wavelengths of 780 nm, 850 nm och 780-670 nm were also used to test the correlation with the three parameters. There was generally a good correlation between biomass and the different indices. Also for the amount of nitrogen there was a good correlation with the indices. For nitrogen concentration in the plants the correlation with the indices was much lower. The highest correlations were found for the indices NDVI, NIR/Green, 780 nm and 780-670 nm, and were used for further analysis of the data. NIR/Green had the highest correlation to all parameters and was therefore used to determine differences between treatments in the field experiments. The area covered by plants in the image analysis had also good correlations to both NDVI and NIR/Green. A problem with measuring crop reflectance was that harvest residues could be a source of reflectance, especially in non tillage treatments. There was also a poor correlation between the indices and the nitrogen concentration. Apart from this, the method worked very well and can definitely be valuable to determine the aboveground biomass and follow the development in field experiments

Demo-scale production of protein-rich fungal biomass from potato protein liquor for use as innovative food and feed products

Innovative food and feed products have recently attracted the attention of both producers and consumers. Filamentous fungi are important biomass producers with their high protein contents. In this study, fungal biomass production from edible potato protein liquor (PPL), generated during starch production processes, was investigated through different fungal strains (Rhizopus oryzae, R. oligosporus, R. delemar, Aspergillus oryzae and Neurospora intermedia). The effects of PPL concentration, incubation time, initial pH, and cultivation conditions (in shake flaks and different scale reactors) were examined to determine the amount of biomass and its crude protein level. It was determined that the fungal biomass produced by R. delemar in industrial scale contained 53% crude protein. For this strain, the amino acid and fatty acid profiles as well as metals (iron, manganese, copper, and zinc) of the produced biomass were also investigated to assess possible use as a food or feed source. The R. delemar fungal biomass can be a promising raw material for feed and food production, for example, considering its protein and fatty acid profiles with 41% essential amino acids and 33% polyunsaturated fatty acids

Ekonomiska fördelar med maskinsamverkan

Sammanfattning Syftet med projektet är att undersöka om det finns ekonomiska fördelar med maskinsamverkan mellan spannmålsproducenter. I fallstudien undersöks fyra gårdar, varav två av gårdarna är belägna i Enköpings kommun och utgör det första maskinsamarbetet. De två andra gårdarna är belägna i Surahammars kommun och är intresserade av att etablera ett maskinsamarbete i framtiden. Maskinkostnadskalkyler har upprättats för varje gård innan och efter ett inträde i maskinsamarbetet. Kalkylerna har sedan jämförts för att se vilka ekonomiska effekter ett samarbete bidrar med för respektive gård. Dessutom behandlas effekterna av vad ett eventuellt samarbete genererar när det gäller kapitalkostnad, läglighetskostnad, kostnad för att hyra in maskiner och de totala maskinkostnader samt sociala aspekter. Studien visar att kapitalkostnaden minskar på samtliga fyra fallgårdar då de ingår i ett maskinsamarbete. Kapitalkostnaden minskade med emellan 467 till 1508 kronor per hektar. Läglighetskostnaden ökade på tre av gårdarna med som mest 161 kronor per hektar, men minskade i ett av fallen med 55 kronor per hektar. Kostnaden för att hyra in sin samarbetspartner för körslor varierade beroende på hur mycket maskiner som avyttras och skiljde därför kraftigt mellan gårdarna. Variationen är från 406 kronor per hektar till 1 578 kr per hektar. Sammantaget blev totalkostnaden lägre för alla gårdar och som mest minskade kostnaden med 606 kronor per hektar och som minst 183 kronor per hektar. Samtliga lantbrukare framhäver de sociala aspekterna som en viktig del i maskinsamarbetet: De positiva aspekterna som uppkommit med samarbete var enligt Gård 1 att ” Det är mer drag när man är några stycken, man blir mer effektiv”. Enligt Gård 2 upplevde han att det var ”Bättre fart på sådd och tröskning”. Det positiva som Gård 3 ser med ett samarbete är den gemensamma planeringen. Han lyfte även fram de sociala aspekterna som något positivt med ett samarbete. Lantbrukaren på Gård 4 anser att ett samarbete skulle vara positivt för hans son som numera driver det praktiska i lantbruket. För sonens del upplevde lantbrukaren att det både var socialt och arbetsmässigt positivt med ett samarbete.Abstract This project aims to investigate whether there are economic benefits to machinery interaction between grain producers. The case study examines four farms; two of the farms are located in the county of Enköping and is the first machine cooperation of the study. The other two farms are located in the county of Surahammar and are interested to establish machinery cooperation in the future. Machine cost calculations made for each farm before and after machinery cooperation. The calculations are then compared to see the economic impact of cooperation contributes to each farm. It also deals with the effects of what a possible cooperation generates in terms of capital, cost of timeliness, cost for the hire of machines and the total machinery cost, and social aspects. The study shows that the cost of capital decreases in all four cases when the farms participate in machinery cooperation. The cost of capital reduces between a ranging from 467 to 1508 SEK per hectare. Timeliness costs increased in three of the farms up to 161 SEK per hectare, but decreased in one case by 55 SEK per hectare. The cost of hiring a partner for contract work varied depending on how much equipment disposed of and therefore differed significantly between farms. The variation between the farms starts from 406 SEK per hectare up to 1578 SEK per hectare. Overall, the total cost was lower for all farms. By the machine cooperation the farms of the study managed to lower their machine cost from 183 SEK per hectare up to 606 SEK per hectare. All farmers emphasize the social aspects as an important part of the machinery cooperation: The positive aspects arising from the collaboration was as a farm that "There is more action when you are few, it becomes more efficient". According to Farm 2, he felt that it was "more action in activities as sowing and harvesting”. The positive aspect for farm 3 is collaboration in the matter of planning the work. He also addressed the social aspects as an important role of machinery cooperation. The farmer on Farm number 4 believes that cooperation would be beneficial for his son who now runs the practice of the farm. For his son's part the farmer experienced that machinery cooperation played an import role for both work and social aspects

JJ-factors for self-interacting dark matter in 20 dwarf spheroidal galaxies

Dwarf spheroidal galaxies are among the most promising targets for indirect dark matter (DM) searches in $\gamma$-rays. The $\gamma$-ray flux from DM annihilation in a dwarf spheroidal galaxy is proportional to the $J$-factor of the source. The $J$-factor of a dwarf spheroidal galaxy is the line-of-sight integral of the DM mass density squared times $\langle \sigma_{\rm ann} v_{\rm rel} \rangle/(\sigma_{\rm ann} v_{\rm rel})_0$, where $\sigma_{\rm ann} v_{\rm rel}$ is the DM annihilation cross-section times relative velocity $v_{\rm rel}=|{\bf v}_{\rm rel}|$, angle brackets denote average over ${\bf v}_{\rm rel}$, and $(\sigma_{\rm ann} v_{\rm rel})_0$ is the $v_{\rm rel}$-independent part of $\sigma_{\rm ann} v_{\rm rel}$. If $\sigma_{\rm ann} v_{\rm rel}$ is constant in $v_{\rm rel}$, $J$-factors only depend on the DM space distribution in the source. However, if $\sigma_{\rm ann} v_{\rm rel}$ varies with $v_{\rm rel}$, as in the presence of DM self-interactions, $J$-factors also depend on the DM velocity distribution, and on the strength and range of the DM self-interaction. Models for self-interacting DM are increasingly important in the study of the small scale clustering of DM, and are compatible with current cosmological observations. Here we derive the $J$-factor of 20 dwarf spheroidal galaxies from stellar kinematic data under the assumption of Yukawa DM self-interactions. $J$-factors are derived through a profile Likelihood approach, assuming either NFW or cored DM profiles. We also compare our results with $J$-factors derived assuming the same velocity for all DM particles in the target galaxy. We find that this common approximation overestimates the $J$-factors by up to one order of magnitude. $J$-factors for a sample of DM particle masses, self-interaction coupling constants and density profiles are provided electronically, ready to be used in other projects.Comment: 10 pages, 3 figures and 2 table

Rapid effects of progesterone on ciliary beat frequency in the mouse fallopian tube

<p>Abstract</p> <p>Background</p> <p>The physiological regulation of ciliary beat frequency (CBF) within the fallopian tube is important for controlling the transport of gametes and the fertilized ovum. Progesterone influences gamete transport in the fallopian tube of several mammalian species. In fallopian tubes isolated from cows, treatment with 20 micromolar progesterone caused a rapid reduction of the tubal CBF. The aims of this study were to establish methodology for studying fallopian tube CBF in the mouse, as it is an important model species, and to investigate if progesterone rapidly affects the CBF of mice at nM concentrations.</p> <p>Methods</p> <p>A method to assess tubal CBF of mice was developed. Fallopian tubes were dissected and the tissue was cut in small pieces. Tissue samples with moving cilia were located under an inverted bright field microscope and held still against the bottom of a petri dish by a motorized needle system. Images were acquired over 90 minutes at 35 degrees C with a high-speed camera and used for assessing changes in the CBF in response to the addition of hormone.</p> <p>Results</p> <p>The baseline CBF of the mouse fallopian tube was 23.3 +/- 3.8 Hz. The CBF was stable over at least 90 minutes allowing establishment of a baseline frequency, addition of hormone and subsequent recordings. Progesterone at concentrations of 20 micromolar and 100 nM significantly reduced the CBF by 10% and 15% respectively after 30 minutes compared with controls.</p> <p>Conclusions</p> <p>The present study demonstrates that the mouse, despite its small size, is a useful model for studying the fallopian tube CBF ex vivo. The rapid reduction in CBF by 100 nM progesterone suggests that gamete transport in the fallopian tube could be mediated by progesterone via a non-genomic receptor mechanism.</p

Production of fungal biomass from oat flour for the use as a nutritious food source

Fermentation can be a powerful tool for developing new sustainable foods with increased nutritional value and fermented microbial biomass derived from filamentous fungi is a promising example. This study investigates the nutritional profile of edible Aspergillus oryzae biomass produced under submerged fermentation (SmF) using oat flour as a substrate. The fermentation occurred in a 1m3 airlift bioreactor during 48 h at 35 \ub0C and the nutritional profile of the produced fungal biomass in terms of amino acids, fatty acids, minerals (Fe, Zn, Cu, Mn), vitamins (E, D2), and dietary fiber was compared to oat flour as well as pure fungal biomass grown on semi-synthetic medium. The total amount of amino acids increased from 11% per dry weight (dw) in oat flour to 23.5% dw in oat fungal biomass with an improved relative ratio of essential amino acids (0.37 to 0.42). An increase in dietary fibers, minerals (Fe, Zn, Cu), vitamin E, as well as vitamin D2 were also obtained in the oat fungal biomass compared to oat flour. Moreover, the short chain omega-3 α-linolenic acid (ALA) and omega-6 linoleic acid (LA) values increased from 0.6 to 8.4 and 21.7 to 68.4 (mg/g dry weight sample), respectively, in oat fungal biomass. The results indicate that fungal biomass grown on oat flour could have a potential application in the food industry as a nutritious source for a wide variety of products