No description available.

No description available.

We investigate the infrared behaviour of the gluon propagator in Quantum Chromo- dynamics (QCD). A natural framework for such a non-perturbative study is the complex of Schwinger-Dyson equations (SDE).The possible infrared behaviour of the gluon, found by self-consistently solving the approximate boson SDE, is studied analytically. We find that only an infrared enhanced gluon propagator, as singular as 1/p(^4) as p(^2) → 0, is consistent and demonstrate why softer solutions, that others have found, are not allowed. Reassuringly the consistent, enhanced infrared behaviour is indicative of the confinement of quarks and gluons, implying, for example, area-law behaviour of the Wilson loop operator and forbidding a Kāllen-Lehmann spectral representation of both quark and gluon propagators. We then briefly consider the implications of these results for models of the pomeron. The enhancement of the gluon propagator does however introduce infrared divergences in the SDE and these need to be regularised. So far model forms of the enhanced gluon propagator have been used in studies of dynamical chiral symmetry breaking and hadron phenomenology. Though very encouraging results have been obtained, one might hope to use the gluon propagator obtained directly from non-perturbative QCD to calculate hadron observables. We therefore attempt to eliminate the infrared divergences in the SDEs in a self- consistent way, entirely within the context of the calculational scheme. To do this we introduce an infrared regulator λ in the truncated gluon SDE in quenched QCD. We find that this regulator is indeed determined by the equation and bounded by the QCD-scale Aqcd- Thus it is possible to perform the regularisation within the SDEs. However, we have not been able to choose λ < Aqcd.

This thesis reports the use of a time-series analysis approach to study the catchment hydrological system of the River Ribble. Rain gauge records, radar rainfall estimates and flow data are used in the analysis. The preliminary study consists of the flow forecasting at Reedyford, Pendle Water (82 km2). Flow forecasts generated from the rain gauge records are better than the radar rainfall estimates over this small catchment. However, the catchment response to rainfall is quick and no clear advantages in extending the lead-time of the forecast can be introduced by using an artificial time delayed rainfall input. A non-linear rainfall-flow relationship has been studied using the rain gauge rainfall and flow records at the River Hodder catchment (261 km2). A calibration scheme is used to identify the non-linear function of the catchment as well as the rainfall-flow system model. Although a better time-invariant system model can be identified, the non-linear rainfall-flow process cannot be fully explained by a power law function of effective rainfall. Assuming the dynamic, nonlinear system characteristics of the catchment can be reflected by a time-varying model gain parameter, relationships between the parameter and the flow, and between the parameter and the rainfall can be evaluated. These relationships have been used to improve the flow forecast during storm events. The results indicate, however, that the approach failed to improve the flow forecast near the peak flow condition. Radar data have been incorporated to forecast the flow at Jumbles Rock (1053 km2) and Samlesbury (1140 km2), River Ribble. The radar data calibrated by the Lancaster University Adaptive Radar Calibration System appears to produce better flow forecasts than the standard radar data product calibrated by the Meteorological Office. The proposed flow forecasting scheme generates better forecasts than the current system operated by the National Rivers Authority, North West Region.

No description available.

This work aimed to evaluate long-term changes of selected chemical and physical parameters of rainwater from their own rain gauge stations Stropnicko. Chemical and physical parameters influence the rate of loss of substance in the landscape through the soil environment. In particular, the amount and concentration of dissolved sulphates and nitrates, affecting the value of the current pH. Samples were taken from their own rain gauge stations Stropnicko. Names of stations from which samples were taken are Horní Stropnice, Nakolice, Paseky and Nové Hrady. Rainfall were measured between the years 2005-2011 and were subjected to chemical analysis.

Um das mikroskopische Verhalten der Gravitation zu beschreiben, ist es nötig, Quantenfeldtheorie und allgemeine Relativitätstheorie in einer vereinheitlichten Sprache zu formulieren. Eine Möglichkeit dieses Problem anzugehen ist es, die Punktteilchen der Quantenfeldtheorie durch fadenförmige Strings zu ersetzen. Allerdings erfordert die mathematische Konsistenz, dass sich die String in höherdimensionalen Raum-Zeiten bewegen; dies macht es jedoch sehr schwer, physikalische Konsequenzen zu extrahieren. Eine mögliche Lösung dieses Problems ist die Verwendung von String-Dualitäten, welche die Stringtheorie mittels holographischer Beschreibungen mit Eichtheorien auf dem Rand der Raum-Zeit verbinden. Die Dualitäten sind begründete Vermutungen, die die String- und Eichtheorie bei unterschiedlichen Werten der Kopplung gleichsetzen. Nicht zuletzt deshalb ist eine direkte Überprüfung der Dualitäten schwierig durchführbar. Hier hilft jedoch die sehr bemerkenswerte Tatsache, dass eine verborgene Eigenschaft der Vermutungen Integrabilität zu sein scheint, welche eine Extrapolation zwischen starker und schwacher Kopplung ermöglicht. Desweiteren kann das gesamte Spektrum, in gewissen vereinfachenden Grenzfällen, durch einen kompakten Satz von Bethe-Gleichungen ausgedrückt werden. Die Bethe-Gleichungen, welche aus Eichtheorierechnungen hergeleitet und geraten werden, bieten ein exzellentes Hilfsmittel, die vermuteten Dualitäten zu prüfen. Durch das Vergleichen der Vorhersagen der Gleichungen und expliziten Berechnungen in der Stringtheorie erhält man starke Argumente für die Gültigkeit der Vermutung und der angenommenen Integrabilität. / In this thesis we study superstring theory on AdS$_5\, \times\,$S$^5$, AdS$_3\,\times\,$S$^3$ and $\adsfour$. A shared feature of each theory is that their corresponding symmetry algebras allows for a decomposition under a $\mathbb{Z}_4$ grading. The grading can be realized through an automorphism which allows for a convenient construction of the string Lagrangians directly in terms of graded components. We adopt a uniform light-cone gauge and expand in a near plane wave limit, or equivalently, an expansion in transverse string coordinates. With a main focus on the two critical string theories, we perform a perturbative quantization up to quartic order in the number of fields. Each string theory is, through holographic descriptions, conjectured to be dual to lower dimensional gauge theories. The conjectures imply that the conformal dimensions of single trace operators in gauge theory should be equal to the energy of string states. What is more, through the use of integrable methods, one can write down a set of Bethe equations whose solutions encode the full spectral problem. One main theme of this thesis is to match the predictions of these equations, written in a language suitable for the light-cone gauge we employ, against explicit string theory calculations. We do this for a large class of string states and the perfect agreement we find lends strong support for the validity of the conjectures.

The manufacturing industry has an important role in Sweden's economy and has been producing high quality goods that are exported all over the world for a long time. By using modern technologies such as advanced warehouse systems and digital tools, companies can increase productivity and reduce costs. An example of such modern technology is Automatic Speech Recognition (ASR). Most of the previous research conducted in the field of ASR has focused on analyzing and addressing various kind of problems related to the performance of an ASR-system. Furthermore, there are also a number of studies regarding how ASR has been used in the manufacturing industry, and more specifically, to facilitate order picking. In this work, the use of speech recognition was investigated as a possible method to facilitate and streamline the inventory process. To investigate this, a prototype for a web application has been developed. The application enables a user, through speech recognition, to speech the article number together with the available quantity in the warehouse. Subsequently, the user receives a confirmation both visually and through sound of which the application automatically registers it in the Monitor ERP software. Data has been collected by observing user tests and conducting interviews with indi-viduals who all have some connection to the warehouse at different manufacturing companies. The results indicated that the inventory process could become more ef-fective by using the application. However, some deficiencies were identified during the user tests, which means that the prototype needs further development and increased robustness to be used as a tool during inventory management. / Tillverkningsindustrin är viktig del av Sveriges ekonomi och har under en lång tid producerat högkvalitativa varor som exporteras över hela världen. Genom att använda moderna teknologier som avancerade lagersystem och digitala verktyg, kan företagen öka produktiviteten och minska kostnaderna. Ett exempel på en sådan modern teknologi är Automatic Speech Recognition (ASR). Inom området ASR har en betydande del av den tidigare forskningen ägnats åt att analysera och adressera olika problem relaterade till prestandan hos ett ASR-system. Vidare så finns det även ett antal arbeten kring hur ASR använts inom tillverknings-industrin, och mer specifikt, till att effektivisera orderplockningsprocessen inom in-dustrin. I det här arbetet undersöktes huruvida röststyrning kan användas som ett verktyg för att underlätta samt effektivisera inventeringsprocessen. Detta genomfördes tillsam-mans med företaget Monitor ERP, där en prototyp till en webbapplikation har utvecklats. Prototypen ska med hjälp av röststyrning möjliggöra för en användare att säga artikelnummer samt vilket antal som finns i lagret. Därefter ska användaren få en bekräftelse både visuellt och genom ljud, varav applikationen automatisk registrerar in det till Monitors system. Data har samlats in genom att observera användartester samt utföra intervjuer med personer som alla har någon koppling till lagret på olika tillverkningsföretag. Resultatet visade på att inventeringsprocessen kan bli effektivare genom att utföra inventering med hjälp av applikationen. Däremot upptäcktes en del brister under användartesterna vilket betyder att prototypen behöver utvecklas och bli mer robust för att kunna användas som verktyg under inventering.

Avhandlingen tar sin utgångspunkt i två uppslagsord i Svenska Akademiens Ordlista 2006: bautasten och bauta-. Övergripande syfte är att beskriva och förklara lexikala förändringar hos ord bildade med bauta(-) i svenskan under perioden 1664–2006, med särskild hänsyn till dessa förändringars relation till ordens etableringsgrad. Materialet består av 838 belägg för ord bildade med baut- eller böt-, och därutöver undersöks 30 ordböcker. Ordet bautasten är ett isländskt lånord i svenskan. Undersökningen av fornvästnordiska ord visar att bautasteinn kan vara ’sten som är slagen ned i jorden’ eller ’sten rest över en fallen krigare’, två betydelser som kan sammanföras i betydelsen ’minnessten’. Denna betydelse framträder också tydligt i samtliga texter. Historiens höga status under stormaktstiden har haft stor betydelse för att ordet bautasten lånades in i svenskan år 1664. Språkstrukturella faktorer har sannolikt lett till att ordet har uppmärksammats och att det har kunnat användas i svenskan. Under perioden 1664–1790 har etableringsgraden hos bautasten inte har varit hög, men vissa tecken tyder på att den höjs under perioden. Fram till ca 1900 stiger etableringsgraden hos bautasten, men den avtar sedan fram till 1973. I avhandlingen antas att ordets växlande etableringsgrad har varit beroende av synen på historien. I början av 1970-talet stiger etableringsgraden åter hos bautasten och 1985 finns första belägget för bauta- som förstärkande förled, vilket med stor sannolikhet har sin orsak att söka hos den stora populariteten hos och spridningen av seriealbumet Asterix. Förleden bauta- har visat sig vara mycket användbar som förstärkande förled. I materialet finns 3 ord bildade med bauta(-) som inte är etablerade i språksamfundet. / The starting point for the dissertation is two entry words in Svenska Akademiens Ordlista (SAOL 13, 2006): bautasten and bauta-. The overall purpose is to describe and explain lexical changes in words created with bauta(-) in the Swedish language during 1664–2006, placing particular em¬phasis on these changes in relation to the degree of establish¬ment. The material consists of 838 pieces of evidence of words created with baut- or böt- and, in addition, 30 dictionaries are exam¬ined. The word bautasten (‘menhir’, ‘standing stone’) is an Icelandic loan word in the Swedish lan¬guage. The examination of Old West Norse words shows that bautasteinn can be ’sten som är slagen ned i jorden’ (‘stone beaten into the ground’) or ’sten rest över en fallen krigare’ (‘stone erected over a fallen warrior’), two meanings which can be brought together in the meaning ’minnessten’ (‘memorial monument’). This meaning also clearly appears in all texts. The high status of history during the Swedish Age of Greatness was significant for the inclu¬sion of the word bautasten into the Swedish language in 1664. Language-structural factors have likely lead to the word being noticed as well as made it possible to use in the Swedish language. During 1664–1790, the degree of establishment of bautasten was not high, but there are indi¬cations that it increased during the period. Until about 1900, the degree of estab¬lish¬ment of bautasten increased, but then it decreased up until 1973. In the disserta¬tion it is assumed that the varying degree of establishment has been dependent on the view of history. In the beginning of the 1970s, the degree of establishment of bautasten increased once again and in 1985, the first instance of bauta- as an augmentative prefix appears, which most likely can be attributed to the great popularity and wide spread of the cartoon magazine Asterix. The prefix bauta- has proven to be very usable as an augmentative. There are 3 words created with bauta(-) in the material that are not established in the language community

Fake news, or information disorder, is a societal problem that could be partially remedied by automatic detection tools. While still a young research field many such tools have been proposed in academic writing. This systematic mapping study gives an overview of the current research in Natural Language Process-based fake news detection utilising Machine Learning and Neural Network classification algorithms in regards to which classification algorithms have been studied and which datasets have been used. Furthermore, we attempt to make a generalised description of the performance (measured in f-score and accuracy) of the most commonly occurring classification algorithms. From a corpus of 124 research articles and other scientific texts we identify 63 different datasets mainly written in English, and 116 different classification algorithms. The seven most commonly occurring algorithms (Random Forest, Logistic Regression, Support Vector Machine, Decision Tree, Long Short- TermMemory, K-Nearest Neighbors, Convolutional Neural Network) together make up almost 50% of all algorithm occurences in the article corpus. For these seven, the ten occurrences with the best performance are listed. Out of the datasets, the six most common datasets (ISOT, FakeNewsNet, Patwa 2021, LIAR, Bisaillon, and UTK-MLC) together make up 44% of all dataset occurrences. Apart from English, the represented languages were mainly Chinese (Mandarin), Portugese, Indonesian, Bangla, and Albanian. / Olika typer av desinformation (så kallade fake news), är ett problem för dagens samhälle. En av flera möjliga dellösningar på problemet utgörs av automatiserad fake news-detektion. Trots att detta forskningsfält är relativt nytt finns det en uppsjö av olika föreslagna modeller för automatiserad fake news-detektion. Denna systematiska kartläggning syftar till att ge en överblick över den aktuella forskningen inom Natural Language Processing-baserad automatiserad fake news-detektion med klassifikationsalgoritmer både inom maskininlärning och neurala nätverk. Översikten avser vilka klassifikationsalgoritmer samt vilka dataset som förekommer inom forskningen. Vidare försöker vi göra en generell beskrivning av prestandan hos de vanligast förekommande klassifikationsalgoritmerna, mätt i accuracy och f-score. Kartläggningen omfattar en samling på 124 artiklar och andra vetenskapliga texter, ur vilka vi identifierade 63 förekommance dataset och 116 olika förekommande klassifikationsalgoritmer. De sju vanligast förekommande algoritmerna (Random Forest, Logistic Regression, Support Vector Machine, Decision Tree, Long-Short Memory Network, K-Nearest Neighbors, Convolutional Neural Network) utgör tillsammans 49% av alla förekomster inom artikelsamlingen. Vi har tagit ut santliga förekomster av prestandaresultat för dessa sju algoritmer, och listat de tio bästa prestandaresultaten för var och en av de sju algoritmerna. De sex vanligast förekommande dataseten (ISOT, FakeNewsNet, Patwa 2021, LIAR, Bisaillon, and UTK-MLC) utgör tillsammans 44% av alla förekomster. Engelska var med stor marginal det vanligast förekommande språket inom dataseten, andra språk som förekom var kinesiska (mandarin), portugisiska, indonesiska, bangla, och albanska.