A low-emissions power generator comprising a solid oxide fuel cell coupled to a gas turbine has been developed by Rolls-Royce Fuel Cell Systems. As part of the cycle, a fraction of the unreacted fuel (the off-gas) and oxidizer streams is reacted in a burner, which is the main source of pollutant formation. In this thesis a computational model of the burner has been developed which captures the formation of NOx and the oxidation of CO. This model gives accurate predictions at low computational cost, making it suitable for use as a design tool in future burner design optimization through parametric studies. A key factor in increasing computational efficiency was the development of a reduced H2/CO/N2 kinetic mechanism; from a starting mechanism of 30 species to 10 and 116 reactions to 6. The results of laminar opposed-flow diffusion flames have been used to validate the reduced mechanism. Several different turbulent combustion models have been evaluated by creating an interface between the reduced kinetic mechanism and the commercial CFD solver FLUENT. Comparison of model predictions with well-characterized turbulent syngas flames, which share a similar fuel composition to the experimental work conducted on the off-gas burner, shows acceptable agreement. These studies have demonstrated the sensitivity of modelling constants. Improved predictions were achieved by calibrating these constants and including radiative heat losses. Following suitable modification to reflect the predominantly laminar flow present in the current burner design, the relevant modelling approaches were applied to the off-gas burner. Comparison was made to previous detailed measurements, showing that the important trends of NOx and CO are captured in general. The model was extended to high pressure conditions, similar to those in the actual off-gas burner, with the emissions predictions within design limits. The outcome of this work is a fast, accurate design tool for CFD which has capabilities to simulate beyond the laminar burner studied here. It may be applied to more general types of off-gas/syngas burners where turbulence-chemistry interaction is expected to be more significant.

The goal of this thesis is to design and implement a library for data synchronization between multiple client's devices in the context of the ecosystem of a single application targeting the iOS, iPadOS or MacOS operating system. The work focuses on the simple integration of the library into existing applications using the Realm database system and on the simple way to connect the user interface with the synchronization process. I solved the chosen problem by designing a synchronization protocol primarily based on log synchronization to distribute changes between the client and the server, implementing a library to monitor changes in the client's database and distribute them to the server, and implementing a server library to integrate received changes and distribute them with help of notifications. The solution provides an easy way to implement data synchronization between multiple devices using custom database server and with the ability to define how to handle new changes of objects presented in the user interface during the synchronization. Created library can be quickly and easily integrated and thus effectively speed up the application development process.

Combine harvesters are used to gather plants from the field and separate them into the components of value, the grain and the straw. The optimal utilization of existing combine potential is an inevitable task to maximize harvest efficiency and hence to maximize profit. The only way to optimize the threshing and separation processes during harvest is to adjust the combine settings to existing conditions. Operating permanently at optimal harvest efficiency can only be achieved by an automatic control system. However, for reasons of transparency and due to lack of sensors, the approach in this thesis is a combined development of an interactive and an automatic control system for combine process optimization. The optimization of combine processes is a multi-dimensional and multi-objective optimization problem. The objectives of optimization are the harvest quality parameters. The decision variables, the parameters that can be modified, are the combine settings. Analytical optimization methods require the existence of a model that provides function values in dependence of defined input parameters. A comprehensive quantitative model for the input-output-behavior of the combine does not exist. Alternative optimization methods that handle multi-dimensional and multi-objective optimization problems can be found in the domain of Artificial Intelligence. In this work, knowledge acquisition was performed in order to obtain expert knowledge on combine process optimization. The result is a knowledge base with six adjustment matrices for different crop and combine types. The adjustment matrices contain problem oriented setting adjustment recommendations in order to solve single issues with quality parameters. A control algorithm has been developed that is also capable of solving multiple issues at the same time, utilizing the acquired expert knowledge. The basic principle to solve the given multi-objective optimization problem is a transformation into one-dimensional single-objective optimization problems which are solved iteratively. Several methods have been developed that are applied sequentially. In simulation, the average improvement from initial settings to optimized settings, achieved by the control algorithm, is between 34.5 % and 67.6 %. This demonstrates the good performance of the control algorithm.

No description available.

BACKGROUND: Accurate clinical prediction supports the effective treatment of alcohol use disorder (AUD) and other psychiatric disorders. Traditional statistical techniques have identified patient characteristics associated with treatment outcomes. However, less work has focused on systematically leveraging these associations to create optimal predictive models. The current study demonstrates how machine learning can be used to predict clinical outcomes in people completing outpatient AUD treatment. METHOD: We used data from the COMBINE multisite clinical trial (n = 1383) to develop and test predictive models. We identified three priority prediction targets, including (1) heavy drinking during the first month of treatment, (2) heavy drinking during the last month of treatment, and (3) heavy drinking between weekly/bi-weekly sessions. Models were generated using the random forest algorithm. We used "leave sites out" partitioning to externally validate the models in trial sites that were not included in the model training. Stratified model development was used to test for sex differences in the relative importance of predictive features. RESULTS: Models predicting heavy alcohol use during the first and last months of treatment showed internal cross-validation area under the curve (AUC) scores ranging from 0.67 to 0.74. AUC was comparable in the external validation using data from held-out sites (AUC range = 0.69 to 0.72). The model predicting between-session heavy drinking showed strong classification accuracy in internal cross-validation (AUC = 0.89) and external test samples (AUC range = 0.80 to 0.87). Stratified analyses showed substantial sex differences in optimal feature sets. CONCLUSION: Machine learning techniques can predict alcohol treatment outcomes using routinely collected clinical data. This technique has the potential to greatly improve clinical prediction accuracy without requiring expensive or invasive assessment methods. More research is needed to understand how best to deploy these models.

Cette thèse porte sur la synthèse et l'étude des propriétés structurales et magnétiques de perovskites RBaMn2O6-d (où d = 0 et 0,5).<br /> En ce qui concerne le composé YBaMn2O6, les mesures par DSC indiquent que celui-ci subit trois transitions : deux autour de 500K et la troisième à 750K. L'étude par diffraction des rayons X et de neutrons a montré que la phase de plus haute température cristallisait dans le groupe P4/nbm. Les diffractogrammes de rayons X et de neutrons ne présentent qu'un seul changement alors que deux transitions sont observées par DSC au voisinage de 500K. La phase intermédiaire a été affinée dans le groupe d'espace C2/m. La phase d'ordre de charges (en dessous de 500K) étant de basse symétrie, nous avons réalisé un affinement combiné rayons X-neutrons. Les résultats obtenus indiquent un écart de seulement 15% par rapport à un ordre de charges idéal Mn3+/Mn4+. L'affinement de la structure magnétique et les mesures de susceptibilité magnétique indiquent la formation de polarons de Zener contenant quatre cations manganèse. <br /> Le composé YBaMn2O5,5 cristallise dans le groupe d'espace Icma, sa maille étant double de celle du composé au lanthane. Ceci est du à l'existence d'une rotation des octaèdres de la structure autour de la direction [001] dans le composé YBaMn2O5,5. L'affinement de la structure magnétique ainsi que les mesures de susceptibilité magnétique indiquent que les spins des cations Mn3+ présents dans la structure sont couplés de manière antiferromagnétique. <br /> L'étude des composés RBaMn2O6 nous a permis d'établir un diagramme de phases en fonction de la terre rare et de la température.

Σκοπός της εργασίας αυτής είναι η μελέτη της επίδοσης κωφών μαθητών σε διάφορα είδη αριθμητικών προβλημάτων. Συγκεκριμένα, η μελέτη των επιδόσεων κωφών μαθητών σε αριθμητικά προβλήματα προσθετικού τύπου σε σχέση με την τάξη που παρακολουθούν, το είδος του προβλήματος, καθώς και η επίδραση της χρήσης Ελληνικής Νοηματικής Γλώσσας στη κατανόηση των προβλημάτων. Τα ερωτήματα στα οποία γίνετε μια προσπάθεια να απαντηθούν είναι: (1) σε ποιό βαθμό η χρήση Ελληνικής Νοηματικής Γλώσσας κατά την εκφώνηση του αριθμητικού προβλήματος διευκολύνει την κατανόηση του και επομένως συμβάλει θετικά στην επίλυση του, (2) σε ποιο βαθμό η επίδοση των μαθητών στα ίδια αριθμητικά προβλήματα διαφοροποιείται ανάλογα με την τάξη, την οποία παρακολουθούν, και την ηλικία τους και (3) εάν το είδος του αριθμητικού προβλήματος σχετίζεται με τη φοίτηση των μαθητών π.χ. εάν κάποια προβλήματα γίνονται κατανοητά σε παιδιά μεγαλύτερης τάξης. Στην έρευνα πήραν μέρος επτά μαθητές (Ν=7) από τα Ειδικά Δημοτικά Σχολεία Κωφών και Βαρηκόων Αργυρούπολης και Πάτρας και 30 μαθητές (Ν=30) από το Δημοτικό Σχολείο Γαλατά Τροιζήνας, οι οποίοι αποτέλεσαν την ομάδα ελέγχου. Τα αποτελέσματα έδειξαν ότι οι κωφοί και οι βαρήκοοι μαθητές παρουσιάζουν χαμηλότερες επιδόσεις στην επίλυση αριθμητικών προβλημάτων τύπου από αυτές των ακουόντων μαθητών ίδιας ηλικίας, ανεξαρτήτως τρόπου επικοινωνίας. Συγκεκριμένα, οι επιδόσεις τους στην περίπτωση που γίνετε χρήση Ε.Ν.Γ. κατά την εκφώνηση των παραπάνω προβλημάτων, παρουσιάζονται αρκετά βελτιωμένες από την περίπτωση της χρήσης γραπτού λόγου. Επιπλέον, οι επιδόσεις των κωφών και βαρήκοων μαθητών της έκτης τάξης, και με τους δύο τρόπους επικοινωνίας, είναι καλύτερες από αυτές των μαθητών της πέμπτης τάξης. Όσον αφορά τις επιδόσεις των κωφών μαθητών στα διάφορα είδη αριθμητικών προβλημάτων, φαίνεται να έχουν καλύτερη επίδοση από όλους στα προβλήματα αυτά, στα οποία δίνονται όλες οι αρχικές ποσότητες και ζητείται η τελική, όπως και σε αυτά που οι λέξεις που χρησιμοποιούνται είναι συνεπείς με τις πράξεις που απαιτούνται για την επίλυση τους. Οι μαθητές της έκτης τάξης παρουσιάζουν καλύτερη επίδοση σε όλα τα υπόλοιπα προβλήματα. Τέλος, τα παραπάνω αποτελέσματα πρέπει να ληφθούν σοβαρά υπόψη από τους δασκάλους και τους μαθηματικούς, ώστε να βελτιώσουν τη διδασκαλία τους με το να χρησιμοποιούν Ελληνική Νοηματική Γλώσσα για να κατανοούν οι μαθητές πλήρως τις διάφορες έννοιες και τη μαθηματική γλώσσα. Επίσης θα πρέπει να βελτιωθεί η αναγνωστική ικανότητα των κωφών γενικότερα ώστε να μπορούν να κατανοούν τα αριθμητικά προβλήματα και να δοθεί περισσότερος χρόνος στη διδασκαλία των μαθηματικών. / The purpose of this assignment was a first study of deaf students' performance in different types of arithmetic problems. Specifically, the study of deaf students' performance on arithmetic problems to comparison with the class monitor, the type of the problem, and the influence of Greek Sign Language use in understanding of these problems. To analyze this, there was an attempt to answer the following questions: (1) to what extent the use of Greek Sign Language in the pronunciation of arithmetic problem makes them easier for understanding and thus contribute positively to their being answered, (2) to what extent the performance of students at the same arithmetic problems varies according to the order, which follow, and their age and (3) whether the type of arithmetic problem associates with the attendance of students, e.g. if some types of problems are more understandable to older children. Seven students (N = 7) of the Special Primary Schools for Deaf and Hard of Hearing of Argyroupolis and Patras participated in this study as well as 30 students (N = 30) of the Elementary School of Galatas Trizoinias, which served as the control group. The results of the study showed that deaf and hard of hearing students are less efficient in solving arithmetic problems than their hearing piers, regardless of the method of communication. Specifically, their performance, when using G.S.L., are presented quite improved than the use of case writing. Moreover, the performance of sixth grade deaf and hard of hearing students, with both modes of communication are better than those of students of fifth grade. Regarding the performance of deaf students in different types of arithmetic problems they seem to have better performance when all the original amounts are given and the final is been asked. Also when the words used in the problems are consistent with the acts required to solve them. The students of sixth grade are better in the problems. Finally, these results should be taken seriously by teachers and mathematicians to improve their teaching, by using Greek Sign Language, so as their students to understand fully the various mathematical concepts and language. Also they should try to improve the reading ability of deaf students in general so that they can understand the arithmetic problems and also give more time to the teaching of mathematics.

This thesis concerns Precision Agriculture (PA) technology which involves methods developed to optimise grain yield by examining data quality and modelling protein/yield relationship of wheat and sorghum fields in central and southern Queensland. An important part of developing strategies to optimisise grain yield is the understanding of PA technology. This covers major aspects of PA which includes all the components of Site- Specific Crop Management System (SSCM). These components are 1. Spatial referencing, 2. Crop, soil and climate monitoring, 3. Attribute mapping, 4. Decision suppport systems and 5. Differential action. Understanding how all five components fit into PA significantly aids the development of data analysis methods. The development of PA is dependent on the collection, analysis and interpretation of information. A preliminary data analysis step is described which covers both non-spatial and spatial data analysis methods. The non-spatial analysis involves plotting methods (maps, histograms), standard distribution and statistical summary (mean, standard deviation). The spatial analysis covers both undirected and directional variogram analyses. In addition to the data analysis, a theoretical investigation into GPS error is given. GPS plays a major role in the development of PA. A number of sources of errors affect the GPS and therefore effect the positioning measurements. Therefore, an understanding of the distribution of the errors and how they are related to each other over time is needed to complement the understanding of the nature of the data. Understanding the error distribution and the data give useful insights for model assumptions in regard to position measurement errors. A review of filtering methods is given and new methods are developed, namely, strip analysis and a double harvesting algoritm. These methods are designed specifically for controlled traffic and normal traffic respectively but can be applied to all kinds of yield monitoring data. The data resulting from the strip analysis and double harvesting algorithm are used in investigating the relationship between on-the-go yield and protein. The strategy is to use protein and yield in determining decisions with respect to nitrogen managements. The agronomic assumption is that protein and yield have a significant relationship based on plot trials. We investigate whether there is any significant relationship between protein and yield at the local level to warrent this kind of assumption. Understanding PA technology and being aware of the sources of errors that exist in data collection and data analysis are all very important in the steps of developing management decision strategies.

The master's thesis is focused on a design of optimal working speed of auger and belt transporter which are parts of Power Flow header for standard type of combine harvester. In the master's thesis author suggest a new simplified theory of crop flow inside the Power Flow header. The thesis contain the factors which can affect the crop flow and comparison between the Power Flow and competitor's header. The thesis also contain geometrical characteristics of crop for four types of cereal.

Zur Funktionsentwicklung und Prozessoptimierung im Bereich Getreideerntetechnik werden verstärkt numerische Berechnungsverfahren wie CFD und DEM eingesetzt. Die Kopplung beider Verfahren im Allgemeinen, sowie die Simulation des Entmischungsprozesses von Korn und Nichtkornbestandteilen in der Reinigungsanlage des Mähdreschers im Speziellen, setzen hohes Prozessverständnis als auch eine strategische Vorgehensweise bei der Prozessabstraktion, der Modellierung der Partikel und der Partikelinteraktion als auch der Wechselwirkung zwischen Partikel und strömender Luft voraus. Im Vortrag wird zunächst die Notwendigkeit und der Nutzen der Simulation im Bereich Erntetechnik diskutiert. Danach erfolgt die Beschreibung der Abstraktion des Entmischungsprozesses von Korn und Nichtkornbestandteilen. Es werden numerische als auch experimentelle Untersuchungen zur Modellierung und Parametrierung der stark nicht-sphärischen biogenen Partikel beschrieben. Besonderes Augenmerk liegt auf der speziellen Untersuchung der Wechselwirkungen und Abhängigkeiten von Partikeleigenschaften. Anschließend werden die Ergebnisse numerischer und experimenteller Untersuchungen des Entmischungsprozesses diskutiert: In einem ersten Schritt erfolgt die Entmischung in einem kleinen, vertikal schwingenden, luftdurchströmten Behälter. Hier werden umfangreiche Parameterstudien und Sensitivitätsanalysen durchgeführt. In einem zweiten Schritt wird die Entmischung in einem in der Breite reduzierten Segment einer Mähdrescherreinigungsanlage durchgeführt. Stets erfolgt der kritische Vergleich zwischen Simulation und Experiment anhand prozessspezifischer Kenngrößen wie Kornverlust, Abscheideeffizienz, Transportgeschwindigkeit u.a. / Numerical simulation methods such as CFD and DEM are increasingly being used for function development and process optimization in the field of grain harvesting technology. The coupling of both methods in general, as well as the simulation of the separation process of grain and non-grain components in the cleaning device of a combine harvester in particular, requires a high level of process understanding as well as a strategic approach to process abstraction, modeling of the particles and particle interaction as well as the interaction between particles and moving air. The speech first discusses the necessity and benefit of simulation in the field of harvesting technology. This is followed by the description of the abstraction of the separation process of grain and non-grain components. Numerical and experimental studies on modeling and parameterization of the strongly non-spherical biogenic particles are described. Particular attention is paid to the special investigation of the interactions and dependencies of particle properties. The results of numerical and experimental investigations of the separation process are then discussed: In a first step, the separation takes place in a small, vertically oscillating, air-flooded box. Extensive parameter studies and sensitivity analyzes are carried out here. In a second step, the separation is carried out in a segment of a combine cleaning device that is reduced in width compared to real width. The critical comparison between simulation and experiment is always carried out using process-specific parameters such as grain loss, separation efficiency, transport speed, etc.