Odderon Exchange from Elastic Scattering Differences between pp and pp−^{-} Data at 1.96 TeV and from pp Forward Scattering Measurements

We describe an analysis comparing the p¯p elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM crosssections, extrapolated to a center-of-mass energy of √s=1.96  TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scatteringamplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound

Utvärdering och utveckling av säkerhetssystem mot tillbakabrand i pellets- och flisutrustningar

There is always some risk of incident associated with the combustion of solid fuels in automatically stoked boilers or stoves. These incidents are of essentially three types: smoke from the burner back into the boiler room (or back into the living room from pellet stoves), gas explosions in the combustion chamber and back burning in the stoker. There can be a number of reasons for these problems, and in many cases such incidents have not been investigated. The Swedish Building Regulations stipulate that firing equipment shall have adequate safety against fire. They also recommend that stokers/burners should have at least two independent safety systems against back burning. The objective of this project has been to analyse such incidents and to test safety systems for pellet and wood chip burners, in order better to understand how they work. It has also included evaluation of the“fireguard” water sprinkler system. The results from the tests with pellet burners showed that the burners that were tested provided relatively good protection against back burning. However, it was found that it was very important how and where the systems (temperature limiter, water sprinkler etc.) were fitted on the burners in order to ensure correct and effective operation of the safety system. One of the key question was also where to position electronic equipment on the burners in order to ensure that it is not exposed to temperatures higher than those for which it is designed. Over the years, there have been major problems with back burning in older designs of wood chip burners using old technology. The chip burner used in this project was of modern type. The test with simulated back burning showed that the water sprinkler stopped the fire. However, for greater safety the water sprinklers should have included two separate water container. The test with the pellets stove showed that the temperature sensor was of crucial importance for safety against back burning in the stove. Back burn occurred in one of the tests, but only after all the stove’s safety systems had been rendered inoperable. The “Fireguard” water sprinkler system performed well in our tests. However, the position of the temperature sensors, and the integrity of their thermal contact, was of crucial importance for how quickly the sprinklers responded. Another water sprinkler (Syr) showed itself to be very slow to respond when its sensor were in poor thermal contact with the surface of the fuel feed chute. Experience from the tests in this project has shown that it is relatively difficult to simulate back burning in boilers and pellet stoves, despite setting up very favourable conditions for such back burning. Although modern burners and pellet stoves are equipped with all the safety systems that can be expected, several incidents still happen every year. This means that continued analysis of incidents and development of safety systems is essential. The results from this project will be included when SP’s P-marking rules for pellet burners, pellet stoves and chip wood burners are next reviewe

Fully Distributed Ubiquitous Information Sharing on a Global Scale for the Internet-of-Things

The Internet-of-Things will require ubiquitous informationsharing between connected things on a global scale, whichexisting systems do not offer. Most current efforts focus on solutionsfor information dissemination, which induce single pointsof failure and introduce unnecessary communication delays. Tothis end we propose the SensibleThings platform, which is afully distributed open source architecture for Internet-of-Thingsbased applications. This article describes the major problems thatInternet-of-Things platforms must address, our technical solutionto these problems, and an evaluation thereof. We also present thecurrent progress and a series of demonstrators, which show thewide range of applications enabled by the platform. Finally, wepresent how the platform will be used in our future research andpotential spin off companies

Risk assessment as a tool for improving external biosecurity at farm level

Background: Biosecurity routines at herd level may reduce the probability of introduction of disease into the herd, but some measures may be regarded as expensive and cumbersome for the farmers. Custom-made measures based on individual farm characteristics may aid in improving the actual application of on-farm biosecurity. The aim of the study was to provide a tool for calculating the effects of different biosecurity measures and strategies on the individual farm level.A simple model was developed to assess the risk of disease introduction and the need for biosecurity measures in individual farms. To illustrate the general applicability of the tool, it was applied to theoretical examples of Swedish cattle and pig farms and diseases endemic in those animal species in the EU, in two scenarios with different between-farm contact patterns.Results: The model illustrated that the most important factors affecting the risk, and the effect of biosecurity measures such as quarantine routines and protective clothing, were the frequency of between- farm contacts and prevalence of the disease. The risk of introduction as well as the effect of biosecurity measures differed between farm types and disease transmission routes. Adapting contact patterns to mitigate a specific disease risk was as important as biosecurity measures for some farm types, but the largest effect was seen when combining biosecurity measures with more planned contact patterns.Conclusions: The risk assessment model proved useful for illustrating the risk of introduction of endemic diseases and the mitigating effect of different biosecurity measures on farm level. Model outputs could be used to justify prioritisation of measures or adapting contact patterns. The theoretic exercise of adjusting model inputs and comparing outputs may help veterinary advisors to understand farm-specific risks and motivate farmers to improve biosecurity in their individual farm, as it can be tailored to each farmer's needs and preferences

Hur valet av förbränningsteknik påverkar utsläpp till luft vid närvärmecentraler vid eldning av spannmål

The aim of this project was to take a closer look at problems connected to combustion of energy grain in a systematic way. The work was restricted to appliances of 100 - 400 kW. Eight users of energy grain were interviewed about there experiences. The majority had smaller problems, besides from relatively many running-in problems, presumably because the instructions for installation and operation were insufficient. Shutdowns were rare and caused by sintering. Burning other cereals than oat often led to sintering. Corrosion is avoided by keeping the flue gas temperature high. Measurements were performed on three boilers for energy grain. Measured carbon monoxide was 70 - 900 mg/Nm3, OGC 0 - 28 mg/Nm3, nitrogen oxides 490 - 945 mg/Nm3 and dust 160 - 440 mg/Nm3. All emissions were higher compared to pellets. Sulphur dioxide and hydrochloric acid were estimated from fuel analysis, and were higher than from combustion of wood. Energy grain does not contribute to global warming and have good properties in the form of high heating value, relatively high density and the grain has a size and form easy to combust. The Swedish Board of Housing, Building and Planning prescribes maximum allowed levels of OGC. The boilers studied in this project had emission well below these limits. For boilers < 500 kW, there are no legislations or recommendation that restrict emissions of dust, nitrogen oxides, sulphur dioxides or hydrochloric acid. The lack of legislation/recommendations makes it difficult to judge whether the emissions are acceptable or not. Today, boilers for energy grain are designed to give low emissions of unburned components and not optimised for low emissions of nitrogen oxides. By changing the design of the burner (it was equipped with three steps with air holes) the emissions were reduced by 27 % without an increase of unburned components. The objective with the steps was to divide the combustion into two zones: one with deficit of oxygen and one rich with oxygen. It is probable possible to reduce the emission even more by dividing the combustion in an even more sophisticated way. Measurements in three different boilers showed that dust emission from one of the boilers that used modulating power regulation was substantially lower than from the other two that were controlled by an on-off thermostat. This may be explained by higher degree of ash pulled by the gas flow at high power, or by lower temperature in the glow bed at low power. However, more data is required to draw general conclusions. Emissions of dust, nitrogen oxides, sulphur dioxide or hydrochloric acid constitute an obstacle for a considerable expansion of energy grain and similar fuels; because the emission will be paid attention to if they increase, especially if they increase in connection to densely populated areas. Therefore, a continuous increase of combustion of energy crops should be accompanied by continuous improvements of combustion technique to reduce the emissions

Specialanpassade kurser för yrkesverksamma ingenjörer : Erfarenheter och upplevelser

I dagens samhälle blir det allt viktigare att fortbilda sig under hela sitt yrkesverksamma liv. För att möta efterfrågan på det livslånga lärandet har Mittuniversitetet utvecklat och genomfört ett antal kurser som riktar sig mot yrkesverksamma ingenjörer. Detta arbete presenterar våra erfarenheter av att ge dessa kurser, med en tyngdpunkt på studenternas upplevelser. Syftet med detta är att bygga upp en vetenskaplig bas för vad vi gör som är bra, men även vad som kan förbättras och förändras. Målsättningen är att göra dessa specialanpassade kurser riktade mot yrkesverksamma ingenjörer så givande och flexibla som möjligt. Våra initiala resultat visar bland annat att studenternas negativa upplevelser ofta var kopplade till antagningsförfarandet och det praktiska genomförandet av kurserna. Man hade svårigheter med att hitta hur man skulle registrera sig på kursen och att tidsramen för registrering kunde vara ett problem. Läroplattformen uppfattades som svår att överblicka och det förekom även viss otydlighet gällande var undervisningen skulle äga rum. Den positiva responsen i utvärderingarna gällde främst det faktiska kursinnehållet, då man ansåg att uppgifter och kursmaterial var givande. Vidare uppskattades kursupplägget, att man kunde kombinera studierna med arbete. Framledes kommer vi att fortsätta med dessa utvärderingar i takt med att kurserna ges, och därefter anpassa vårt mottagande och kommunikationen med studenterna. Även kursupplägget ses över kontinuerligt via den återkoppling vi mottar.