This thesis is to develop a novel consensus algorithm or protocol for multi-agent systems in the event of communication link failure over the network. The structure or topology of the system is modeled by an algebraic graph theory, and defined as a discrete time-invariant system with a second-order dynamics. The communication link failure is governed by a Bernoulli process. Lyapunov-based methodologies and Linear Matrix Inequality (LMI) techniques are then applied to find an appropriate controller gain by satisfying the sufficient conditions of the error dynamics. Therefore, the controller with the calculated gain is guaranteed to drive the system to reach a consensus. Finally, simulation and experiment studies are carried out by using two Mobile Robot Pioneer 3-DXs and one Pioneer 3-AT as a team to verify the proposed work.

One of the protocols used for communication between coaches inside a train is the National Train Bus (NTB). The result of this work is support for diagnostics on the NTB - mainly watching the process data-flow and monitoring of chosen variables distributed along the train, with consideration to their character and validity.

A dissertation submitted to the Faculty of Engineenug, University of the Witwatersrand, in fulfilment. of the requirements for the degree of Master of Science in Engineering, / A multi variable control strategy for a grinding circuit at East Driefontein has been implemented by others and has enabled it to operate under stable conditions. The next development needed was to find conditions under which tne efficiency of the circuit was the greatest. Optimum set points exist for the multi variable controller to keep the circuit at its most efficient state. This project was done to determine these set points, and how it affected the operation of the circuit. The strategy involved the collection of process data, the development of mathematical models and the determination of these optimum set points by simulation, This option reduced interference with routine production operations, which is often a prohibiting factor during any development work on an existing process. The optimum set points were successfully determined, and were compared with previous findings and current plant practice. / AC2017

No description available.

No description available.

Abstract The amount of digital data surrounding us has exploded within the past years. In industry, data are gathered from different production phases with the intent to use the data to improve the overall manufacturing process. However, management and utilization of these huge data sets is not straightforward. Thus, a computer-driven approach called data mining has become an attractive research area. Using data mining methods, new and useful information can be extracted from enormous data sets. In this thesis, diverse industrial problems are approached using data mining methods based on similarity. Similarity information is shown to give an additional advantage in different phases of manufacturing. Similarity information is utilized with smaller-scale problems, but also in a broader perspective when aiming to improve the whole manufacturing process. Different ways of utilizing similarity are also introduced. Methods are chosen to emphasize the similarity aspect; some of the methods rely entirely on similarity information, while other methods just preserve similarity information as a result. The actual problems covered in this thesis are from quality control, process monitoring, improvement of manufacturing efficiency and model maintenance. They are real-world problems from two different application areas: spot welding and steel manufacturing. Thus, this thesis clearly shows how the industry can benefit from the presented data mining methods.

This paper explores the potential of process data distribution in real time using the RTP protocol. Firstly, there is an evaluation of existing protocols that are used for this purpose. Secondly, there is a description of the trio of protocols RTP, RTCP, and RTSP, explained their functions and explored possibilities for their expansion. On the basis of this acquired knowledge, problems which may occur with the distribution of process data by means of RTP are identified and their possible solutions are proposed. To demonstrate the data distribution via RTP, the application, that collects GPS position from the PDA and then provides clients with them, has been designed and implemented. Clients can display these data on the map.

Beim Siegeln von Verpackungen können nicht-qualitätsgerechte Siegelnähte dadurch entstehen, dass sich Teile des Packguts zwischen den zu fügenden Packmittelbahnen befinden. Im Gegensatz zum konventionellen Wärmekontaktsiegeln besteht beim Ultraschallsiegeln die Möglichkeit, für jeden einzelnen Siegelvorgang Prozessdaten zu erfassen. Aus dem Bereich des Ultraschallschweißens ist bekannt, dass sich anhand dieser Daten der Prozess überwachen und dessen Güte bewerten lässt. Die vorliegende Arbeit untersucht den Informationsgehalt dieser Prozessdaten hinsichtlich störungsbehafteter Siegelnähte und leistet damit einen Beitrag zur Verbesserung der Verpackungsqualität und damit im besten Fall auch zu weniger Lebensmittelverlusten. Es wird dazu zunächst eine Systematisierung von möglichen Störprinzipen beim Siegeln hinsichtlich ihrer physikalischen Wirkprinzipe vorgenommen. Darauf aufbauend konnte ein Versuchsstand und eine Methodik zur Untersuchung der Thematik entwickelt werden. Abschließend wurden ausgewählte Störprinzipe untersucht, wobei sich ein sehr starker Packstoff- und Einfluss der Prozessführung herausstellte. Es konnte ein prinzipieller Zusammenhang zwischen Auswirkung einer Störung auf die Nahtqualität und die Prozessdaten gezeigt werden, welcher sich jedoch auf Basis der erarbeiteten Ergebnisse nicht verallgemeinern lässt.

Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / Vita. / Includes bibliographical references. / Ph.D.

Thesis advisor: Matthias von Davier / The transition of major international large-scale assessments (ILSAs) from paper- to computer-based assessments has made process data increasingly available. While process data is potentially valuable for analyzing students’ test-taking behaviors, it also raises ethical concerns and involves considerable costs. This prompts the question: “Does process data add value to the analysis of ILSA data?” In response, this dissertation explores the utility of process data through three studies. Study 1 proposes a multiple-group hierarchical speed-accuracy-revisits model to examine the gender differences in mathematics ability, response speed, revisit propensity, and the relationships among them. The model’s flexibility allows it to be applied in diverse contexts to investigate group differences in test-taking behaviors and achievement beyond gender. Study 2 addresses the overparameterization challenge in ILSA scaling by proposing a new approach: adding process variables to the usual contextual variables and replacing principal component analysis with variable selection for latent regression modeling. The findings show that process variables consistently improved measurement precision; using Lasso, random forests, and ultimately gradient boosting for variable selection achieved or surpassed the measurement precision of the conventional approach but with considerably fewer covariates. Integrating variable selection and process data yielded the highest measurement precision while achieving parsimony, demonstrating the effectiveness of the proposed method. Study 3 investigates students’ test-taking behaviors in the context of girls consistently outperforming boys on average across countries and assessments. Three types of test-taking behaviors were identified through latent class analysis: “Rapid”, “Challenged”, and “Engaged”. Using Bolck-Croon-Hagenaars and three-step methods reveals that girls in the “Rapid” class outperformed boys on average in all countries, while there were no significant gender differences in the “Engaged” class in three of the four countries. The gender gap in reading achievement may diminish to a mild to moderate extent if boys were to behave like girls, highlighting the importance of addressing disengagement issues in ILSAs. Collectively, these three papers advance the use of process data and demonstrate its value for analyzing and reporting results of ILSA data. / Thesis (PhD) — Boston College, 2024. / Submitted to: Boston College. Lynch School of Education. / Discipline: Education.