This study focused on the dynamic behaviour of the freeze lining and slag bath, and the interactions between these components in an ilmenite-smelting furnace process. The purpose of the work was to gain a better understanding of these issues and to ultimately contribute to an improved understanding of the ilmenite-smelting process in its entirety, and to future improvements in the design, operation and control of these processes. A mathematical model of the freeze lining and furnace sidewall was developed. This model was used in isolation for focused characterisation of the dynamic behaviour and interactions of the freeze lining and slag bath. The influences of net power input and slag composition were studied and various aspects of the freeze lining and slag bath were considered. These aspects included freeze lining thickness, temperature distribution through the freeze lining and furnace sidewall, composition distribution through the freeze lining, slag bath temperature and slag bath composition. The thermal response of thermocouples installed in the furnace sidewall to changing conditions on the inside of the furnace was also investigated. A mathematical model of the crust that forms on the slag bath surface was developed. This model was not used in isolation, and was only incorporated into a complete model of the process. A mathematical model of the entire ilmenite-smelting furnace process was constructed. This model incorporated the two models mentioned above and was able to describe the metal bath, slag bath, furnace atmosphere, freeze lining, furnace sidewall and the crust that is sometimes present on top of the slag bath. The model was used to study the influence of changes in operational parameters on the slag bath and freeze lining. The operational parameters that were studied included electrical power and reductant feed rate, both relative to ilmenite feed rate. The influence of severe operational errors and furnace down time were also investigated. Operational errors included loss of all feed while maintain electrical power input, and loss of reductant feed while maintaining power input and ilmenite feed. The above-mentioned studies were conducted by executing numerous experiments with two of the mathematical models. The experimental results were processed into sets of graphs displaying variations in the aspects that were considered. Many valuable insights resulted from the interpretation of these results. One specific aspect that formed part of the scope of this work was the origin of the compositional invariance of the slag close to the stoichiometric M3O5composition. This invariance was studied and a mechanism was proposed that explains the observed behaviour. The proposed mechanism created some questions about other mechanisms in the process. These mechanisms were also considered and elaborated on. The models and results produced in this study provide valuable insights into the behaviour of the ilmenite-smelting process. It also represents a useful foundation for future modelling work, and finally, it presents numerous opportunities for organisations operating ilmenite-smelting furnaces to improve their understanding and even the performance of their processes. / Thesis (PhD (Metallurgical Engineering))--University of Pretoria, 2004. / Materials Science and Metallurgical Engineering / unrestricted

The COVID-19 pandemic has seriously impacted the global economy, especially port trade. The port of Jiujiang was hit hard by the COVID-19 pandemic. Jiujiang port is an important port in China's inland rivers, an important hub of the regional transportation system, and an important port for foreign trade and plays a great role in economic development.This article uses a questionnaire survey to find that the factors affecting ports during the COVID-19 pandemic include an increase in COVID-19 diagnosis, a decline in demand, and rising port costs. These factors are analyzed using the BPMN model and BMC model. The BPMN model describes the container handling process in Jiujiang Port and is used to analyze the increase in COVID-19 diagnosis. BMC's Western Europe tour describes the corporate structure of Jiujiang Port. It is used to analyze the decline in demand and rising port costs.The measures of Jiujiang Port Use electronic communication instead of human contact, Port expansion, and building big data platform are used to deal with these three factors affecting the port. These measures are analyzed using SWOT analysis to analyze their strengths, weaknesses, challenges, and opportunities. Improvements to these measures are proposed. Requiring ships and ports to communicate electronically, build big data platforms, and expand ports were measures taken by Jiujiang Port as response measures to the COVID-19 Pandemic. Recommended measures for digitalization are: provide digital training for employees, increase data communication with other ports and enterprises, make thorough plans, complete the realization of intelligent scenarios, and pay attention to government countermeasures and market changes.

Two of the main needs when developing an information system for an organization are that system analysts know and understand the application domain and that the system properly supports the business processes of the organization. Consequently, elicitation of system requirements from business process models has been acknowledged as a suitable activity to deal with that needs. In addition, system requirements must be linked to subsequent development stages. However, system analysts can face many challenges when performing these activities. They may have problems communicating with customer stakeholders and may need to analyse and operationalize the purpose of the information system. Furthermore, system analysts must bridge the gap between business and system domains for specification of system requirements, specify different types of system requirements and guarantee that their specification is precise, consistent and homogeneous. In relation to object-oriented conceptual modelling-based information system development, system analysts must also avoid potential problems that may arise when a conceptual schema is created from system requirements as part of their link with subsequent development stages. For example, a conceptual schema can be incomplete and/or inconsistent if it is not properly managed. As a solution, this thesis presents a methodological approach for business process-based requirements specification and object-oriented conceptual modelling of information systems. The approach consists of four stages: organizational modelling, purpose analysis, specification of system requirements and derivation of object-oriented diagrams. By following the design research methodology for performing research in information systems, the methodological approach has been designed on the basis of many existing ideas and principles in academia and industry and provides new principles, mechanisms and guidance to address the challenges presented above. / De La Vara González, JL. (2011). Business process-based requirements specification and object-oriented conceptual modelling of information systems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11445

Dynamic modelling and optimization of three different processes namely (a) bulk polymerization of styrene, (b) solution polymerization of methyl methacrylate (MMA) and (c) emulsion copolymerization of Styrene and MMA in batch and semi-batch reactors are the focus of this work. In this work, models are presented as sets of differential-algebraic equations describing the process. Different optimization problems such as (a) maximum conversion (Xn), (b) maximum number average molecular weight (Mn) and (c) minimum time to achieve the desired polymer molecular properties (defined as pre-specified values of monomer conversion and number average molecular weight) are formulated. Reactor temperature, jacket temperature, initial initiator concentration, monomer feed rate, initiator feed rate and surfactant feed rate are used as optimization variables in the optimization formulations. The dynamic optimization problems were converted into nonlinear programming problem using the CVP techniques which were solved using efficient SQP (Successive Quadratic Programming) method available within the gPROMS (general PROcess Modelling System) software. The process model used for bulk polystyrene polymerization in batch reactors, using 2, 2 azobisisobutyronitrile catalyst (AIBN) as initiator was improved by including the gel and glass effects. The results obtained from this work when compared with the previous study by other researcher which disregarded the gel and glass effect in their study which show that the batch time operation are significantly reduced while the amount of the initial initiator concentration required increases. Also, the termination rate constant decreases as the concentration of the mixture increases, resulting rapid monomer conversion. The process model used for solution polymerization of methyl methacrylate (MMA) in batch reactors, using AIBN as the initiator and Toluene as the solvent was improved by including the free volume theory to calculate the initiator efficiency, f. The effects of different f was examined and compared with previous work which used a constant value of f 0.53. The results of these studies show that initiator efficiency, f is not constant but decreases with the increase of monomer conversion along the process. The determination of optimal control trajectories for emulsion copolymerization of Styrene and MMA with the objective of maximizing the number average molecular weight (Mn) and overall conversion (Xn) were carried out in batch and semi-batch reactors. The initiator used in this work is Persulfate K2S2O8 and the surfactant is Sodium Dodecyl Sulfate (SDS). Reduction of the pre-batch time increases the Mn but decreases the conversion (Xn). The sooner the addition of monomer into the reactor, the earlier the growth of the polymer chain leading to higher Mn. Besides that, Mn also can be increased by decreasing the initial initiator concentration (Ci0). Less oligomeric radicals will be produced with low Ci0, leading to reduced polymerization loci thus lowering the overall conversion. On the other hand, increases of reaction temperature (Tr) will decrease the Mn since transfer coefficient is increased at higher Tr leading to increase of the monomeric radicals resulting in an increase in termination reaction.

Ce mémoire de thèse présente une étude fondamentale enrichie par des contributions qui sont articulées autour de la modélisation de processus ainsi qu'un diagnostic de défauts en utilisant l'analyse en composantes principales (ACP). Dans l'objectif d'un choix optimal du modèle ACP, une étude comparative de quelques critères connus dans la littérature nous a permis de conclure que le problème rencontré est souvent lié à une ignorance des variables indépendantes et quasi-indépendantes. Dans ce cadre, nous avons réalisé deux démonstrations mettant en évidence les limitations de deux critères en particulier la variance non reconstruite (VNR). En s'appuyant sur le principe d'une telle variance, nous avons proposé trois nouveaux critères. Parmi eux, deux ont été considérés comme étant empiriques car seule l'expérience permettra de prouver leur efficacité. Le troisième critère noté VNRVI représente un remède à la limitation du critère VNR. Une étude de sa consistance théorique a permis d'établir les conditions garantissant l'optimalité de son choix. Les résultats de simulation ont validé une telle théorie en prouvant ainsi que le critère VNRVI étant plus efficace que ceux étudiés dans cette thèse. Dans le cadre d'un diagnostic de défauts par ACP, l'approche de reconstruction des indices de détection ainsi que celle des contributions ont été utilisées. A travers une étude de généralisation, nous avons étendu le concept d'isolabilité de défauts par reconstruction à tout indice quadratique. / This thesis presents a fundamental study enhanced by some contributions that are focused on process modelling and fault diagnosis using principal components analysis (PCA). In order to find an optimal PCA model, we have concluded through a comparative study of some popular criteria that the problem is often related to an ignorance of the independent and quasi-independent variables. In this framework, we have performed two demonstrations highlighting the limitations of two selection criteria in particular the unreconstructed variance (VNR). Based on the principle of VNR approach, we have proposed three new criteria, among them two methods were considered as empirical criteria because only the experience will prove their effectiveness. However the third one which is noted VNRVI represents a cure for the limitation of the classical VNR criterion. Thus, the conditions that ensure an optimal selection were derived according to a theoretical consistency study of the VNRVI approach. The simulation results have successfully validated the VNRVI criterion by proving that is more effective than the other studied criteria in the present thesis. The reconstruction and contributions approaches were used for fault diagnosis using PCA. According to a unified study, we have extended the fault isolability concept based on the reconstruction method to any detection index which has a quadratic form. Such generalization has allowed us to develop a theoretical fault isolability analysis based on the reconstruction of the combined index versus those of SPE and T2 indices. This analysis has highlighted the advantage of using the combined index for fault isolation.

This diploma thesis is dedicated to the examination of maturity levels of the rescue service of the central bohemian region. Furthermore to using the results of the examination to formulate recomandations in order to ease possible effort of the management to introduce approaches of the process management into the organization. Levels of maturity are examined by the factors identified by Mike Hammer in his PEMM (Process and Enterprise Maturity Model) model. Whole document is logically divided into four parts. The first part consists of detail description of the organization from three different angles. Purpose of the organization, strategic goals of the management and the organizational structure. Second part includes global and detail business process models created by the MMABP (Methodology for Modelling and Analysis of Business Process) by prof. Ing. Václav Řepa Csc. The models are created in the BPMN (Business Process Modelling Notation) and Eriksson-Penker notation. There are also included process interfaces and object lifecycles in the second part. Third part is where the comparison of described reality and the PEMM model factors of maturity is being made. All the maturity levels of the factors are argumented here as well. In the last part of this document, there is a presentation of the recomandations concluded from the previous comparison.

L'industrie actuelle est en plein développement suite à la mise en œuvre du concept de l'industrie 4.0 visant à rendre l'usine une entité intelligente, en combinant les processus et pratiques industriels avec les technologies de l'information et de communication récentes comme les systèmes cyber-physiques et l'internet des objets connectés (IoT), entre autres. Ce développement industriel, ainsi que le besoin d'innover pour atteindre et maintenir la compétitivité favorisent une augmentation phénoménale du volume de données (connue sous le nom de Big Data), rendant ainsi (i) les processus de conception et de supervision des systèmes de plus en plus chaotiques, (ii) les données au sein des organisations de plus en plus difficiles à exploiter et (iii) les ingénieurs de plus en plus perdus lors de la prise de décision. En effet, plusieurs problèmes sont identifiés dans les milieux industriels et qui peuvent être classés en trois catégories : (i) difficultés lors de la recherche, la visualisation et l'échange de l'information, (ii) difficultés lors de la prise de décision et (iii) difficultés lors de la gestion des changements de contexte. A travers ce travail, nous proposons un système d'aide à la décision intelligent et modulaire, dont chacun des quatre modules résout un des problèmes identifiés. Les modules de modélisation et de traçabilité des processus permettent de modéliser les processus et de capturer la façon comment ils sont exécutés. Le module d'aide à la décision permet de proposer le pattern le plus adapté au contexte de la décision ainsi que les paramètres de ses activités les plus significatifs. Le module de gestion des changements contextuels permet de continuellement mettre à jour le module de prise de décision, lui permettant ainsi de tenir compte de l'aspect dynamique du contexte. Le système proposé est entièrement vérifié et à moitié validé dans le contexte du projet Gontrand, visant la supervision intelligente et en temps réel des réseaux de gaz favorisant l'injection du gaz vert. Pour qu'il soit entièrement validé, les performances du système doivent être analysées après l'intégration et l'exploitation de ce dernier dans un milieu industriel réel. / Data sets are growing rapidly because of two things. First, the fourth industrial revolution that aims to transform factories into smart entities in which cyber physical systems monitor the physical processes of the factory. Second, the need to innovate in order to achieve and maintain competitiveness. Due to this huge volume of data (Big Data), (i) design and supervision processes are becoming chaotic, (ii) data within organizations is increasingly becoming difficult to exploit and (iii) engineers are increasingly lost when making decisions. Indeed, several issues are identified in industry: (i) when researching, visualizing and exchanging information, (ii) when making decisions and (iii) when managing contextual changes. Through this research work, we propose an Intelligent and modular Decision Support System (IDSS), where each of the four modules solves one of the identified issues. Process modelling and traceability modules aim to model processes and capture how they are actualy executed. The decision support module proposes the process patterns that best fit the decision context, as well as their most significant activity parameters. The contextual change management module continuously updates the decision-making module, in order to handle the dynamic aspect of the decision context. The proposed system is fully verified and half-validated in the context of the Gontrand project, aiming at intelligent and real-time supervision of gas networks favoring the injection of green gas. In order to be fully validated, the performance of the system must be analyzed after integrating and exploitating it in a real industrial environment.

In the drive towards higher strength alloys, a diverse range of alloying elements is employed to enhance their strength and ductility. Limited solid solubility of these elements in steel leads to segregation during casting which affects the entire down-stream processing and eventually the mechanical properties of the finished product. The work presented in this PhD shows that segregation of alloying elements during casting, particularly aluminium, leads directly to banding in the final product. It has been demonstrated that no significant homogenisation is possible in this alloy within practical time constraints of the industrial thermo-mechanical process. A through-process model was developed to design a thermo-mechanical treatment aimed at reducing the effects of segregation on the formation of banding. A new polynomial function for calculating the local phase transformation temperature (Ae3) between the austenite + ferrite and the fully austenitic phase fields during heating and cooling of steel is presented. Material was produced both with and without banding and used to study the effect upon the mechanical properties. The banded steel variants show a significant reduction in tensile strength for a similar level of ductility compared to non-banded variants. In situ measurement under uniaxial loading using high-energy synchrotron diffraction allowed direct quantification of the impact of the mechanically induced transformation of metastable austenite on the work- hardening behaviour. The results reveal that the mechanically induced transformation of austenite does not begin until the onset of matrix yielding and the experimental evidence demonstrates that the austenite to martensite transformation increases the work-hardening rate of the ferrite phase and delays the onset of Stage-III hardening until the yield point of austenite. The increase in work-hardening rate (and thus work required) supports a driving force approach to transformation induced plasticity. The transformation work required leads to an increase in the macroscopic work-hardening rate after matrix yielding which offsets the decrease in the work-hardening rate in the ferrite and martensite phases up to the UTS. Steels with a high degree of banding do not show this extra contribution due to the more dominant anisotropic effect of martensite bands on the work-hardening of ferrite coupled to increased mechanical austenite stability as a result of increased carbon content. A list of revisions as requested by the examiners is produced on pages 18 and 19 of the thesis for examination. Abstract: In the drive towards higher strength alloys, a diverse range of alloying elements is employed to enhance their strength and ductility. Limited solid solubility of these elements in steel leads to segregation during casting which affects the entire down-stream processing and eventually the mechanical properties of the finished product. The work presented in this PhD shows that segregation of alloying elements during casting, particularly aluminium, leads directly to banding in the final product. It has been demonstrated that no significant homogenisation is possible in this alloy within practical time constraints of the industrial thermo-mechanical process. A through-process model was developed to design a thermo-mechanical treatment aimed at reducing the effects of segregation on the formation of banding. A new polynomial function for calculating the local phase transformation temperature (Ae3) between the austenite + ferrite and the fully austenitic phase fields during heating and cooling of steel is presented. Material was produced both with and without banding and used to study the effect upon the mechanical properties. The banded steel variants show a significant reduction in tensile strength for a similar level of ductility compared to non-banded variants. In situ measurement under uniaxial loading using high-energy synchrotron diffraction allowed direct quantification of the impact of the mechanically induced transformation of metastable austenite on the work- hardening behaviour. The results reveal that the mechanically induced transformation of austenite does not begin until the onset of matrix yielding and the experimental evidence demonstrates that the austenite to martensite transformation increases the work-hardening rate of the ferrite phase and delays the onset of Stage-III hardening until the yield point of austenite. The increase in work-hardening rate (and thus work required) supports a driving force approach to transformation induced plasticity. The transformation work required leads to an increase in the macroscopic work-hardening rate after matrix yielding which offsets the decrease in the work-hardening rate in the ferrite and martensite phases up to the UTS. Steels with a high degree of banding do not show this extra contribution due to the more dominant anisotropic effect of martensite bands on the work-hardening of ferrite coupled to increased mechanical austenite stability as a result of increased carbon content.

The thesis is focused on cooperation between academic and corporate sector, especially on participation of companies in classes and courses at universities through involvement of their employees in teaching. The aim of this thesis is to analyze current ways of corporate sector involvement in practical parts of courses and to design proposals for possible improvements to the current practices used at The Faculty of Informatics and Statistics of The University of Economics, Prague. Analysis was conducted by application of Theory of systems (General System Theory), Soft System Methodology and business process modeling (using BPMN). Based on the conclusions of the analysis three alternatives for possible improvement in the field are specified, two of them are recommended for implementation. Alternatives recommended for implementation are described in greater detail including process design and description and specification of requirements for technical, financial and human resources.

Gerade in den letzten Jahren erfuhr Open Source Software (OSS) eine zunehmende Verbreitung und Popularität und hat sich in verschiedenen Anwendungsdomänen etabliert. Die Prozesse, welche sich im Kontext der OSS-Entwicklung (auch: OSSD – Open Source Software-Development) evolutionär herausgebildet haben, weisen in den verschiedenen OSS-Entwicklungsprojekten z.T. ähnliche Eigenschaften und Strukturen auf und auch die involvierten Entitäten, wie z.B. Artefakte, Rollen oder Software-Werkzeuge sind weitgehend miteinander vergleichbar. Dies motiviert den Gedanken, ein verallgemeinerbares Modell zu entwickeln, welches die generalisierbaren Entwicklungsprozesse im Kontext von OSS zu einem übertragbaren Modell abstrahiert. Auch in der Wissenschaftsdisziplin des Software Engineering (SE) wurde bereits erkannt, dass sich der OSSD-Ansatz in verschiedenen Aspekten erheblich von klassischen (proprietären) Modellen des SE unterscheidet und daher diese Methoden einer eigenen wissenschaftlichen Betrachtung bedürfen. In verschiedenen Publikationen wurden zwar bereits einzelne Aspekte der OSS-Entwicklung analysiert und Theorien über die zugrundeliegenden Entwicklungsmethoden formuliert, aber es existiert noch keine umfassende Beschreibung der typischen Prozesse der OSSD-Methodik, die auf einer empirischen Untersuchung existierender OSS-Entwicklungsprojekte basiert. Da dies eine Voraussetzung für die weitere wissenschaftliche Auseinandersetzung mit OSSD-Prozessen darstellt, wird im Rahmen dieser Arbeit auf der Basis vergleichender Fallstudien ein deskriptives Modell der OSSD-Prozesse hergeleitet und mit Modellierungselementen der UML formalisiert beschrieben. Das Modell generalisiert die identifizierten Prozesse, Prozessentitäten und Software-Infrastrukturen der untersuchten OSSD-Projekte. Es basiert auf einem eigens entwickelten Metamodell, welches die zu analysierenden Entitäten identifiziert und die Modellierungssichten und -elemente beschreibt, die zur UML-basierten Beschreibung der Entwicklungsprozesse verwendet werden. In einem weiteren Arbeitsschritt wird eine weiterführende Analyse des identifizierten Modells durchgeführt, um Implikationen, und Optimierungspotentiale aufzuzeigen. Diese umfassen beispielsweise die ungenügende Plan- und Terminierbarkeit von Prozessen oder die beobachtete Tendenz von OSSD-Akteuren, verschiedene Aktivitäten mit unterschiedlicher Intensität entsprechend der subjektiv wahrgenommenen Anreize auszuüben, was zur Vernachlässigung einiger Prozesse führt. Anschließend werden Optimierungszielstellungen dargestellt, die diese Unzulänglichkeiten adressieren, und ein Optimierungsansatz zur Verbesserung des OSSD-Modells wird beschrieben. Dieser Ansatz umfasst die Erweiterung der identifizierten Rollen, die Einführung neuer oder die Erweiterung bereits identifizierter Prozesse und die Modifikation oder Erweiterung der Artefakte des generalisierten OSS-Entwicklungsmodells. Die vorgestellten Modellerweiterungen dienen vor allem einer gesteigerten Qualitätssicherung und der Kompensation von vernachlässigten Prozessen, um sowohl die entwickelte Software- als auch die Prozessqualität im OSSD-Kontext zu verbessern. Desweiteren werden Softwarefunktionalitäten beschrieben, welche die identifizierte bestehende Software-Infrastruktur erweitern und eine gesamtheitlichere, softwaretechnische Unterstützung der OSSD-Prozesse ermöglichen sollen. Abschließend werden verschiedene Anwendungsszenarien der Methoden des OSS-Entwicklungsmodells, u.a. auch im kommerziellen SE, identifiziert und ein Implementierungsansatz basierend auf der OSS GENESIS vorgestellt, der zur Implementierung und Unterstützung des OSSD-Modells verwendet werden kann. / In recent years Open Source Software (OSS) has become more widespread and its popularity has grown so that it is now established in various application domains. The processes which have emerged evolutionarily within the context of OSS development (OSSD – Open Source Software Development) display, to some extent, similar properties and structures in the various OSSD projects. The involved entities, e.g., artifacts, roles or software tools, are also widely comparable. This leads to the idea of developing a generalizable model which abstracts the generalizable development processes within the context of OSS to a transferable model. Even the scientific discipline of Software Engineering (SE) has recognized that the OSSD approach is, in various aspects, considerably different from traditional (proprietary) models of SE, and that these methods therefore require their own scientific consideration. Numerous publications have already analyzed individual aspects of OSSD and formulated theories about the fundamental development methods, but to date there is still no comprehensive description of the typical processes of OSSD methodology based on an empirical study of existing OSSD projects. Since this is a precondition for the further scientific examination of OSSD processes, a descriptive model of OSSD processes is obtained on the basis of comparative case studies and described in a formalized manner with UML modeling elements within the context of this dissertation. The model generalizes the identified processes, process entities and software infrastructures of the analyzed OSSD projects. It is based on a specially developed meta model which identifies the entities to be analyzed and describes the modeling viewpoints and elements which are used for the UML-based description of the development processes. Another procedure step includes the further analysis of the identified model in order to display the implications, and the potential for optimization. For example, these encompass the insufficient planning and scheduling capability of processes or the observed tendency of OSSD actors to carry out various activities at different intensities depending on the subjectively perceived incentives which leads to some processes being neglected. Subsequently, the optimization targets which address these inadequacies are displayed, and an optimization approach for the improvement of the OSSD model is described. The approach incorporates the expansion of the identified roles, the introduction of new or the expansion of already identified processes and the modification or expansion of artifacts of the generalized OSSD model. The presented model enhancements serve, above all, to increase quality assurance and to compensate neglected processes in order to improve developed software quality as well as process quality in the context of OSSD. Furthermore, software functionalities are described which expand the existing identified software infrastructure and should enable an overall, software-technical support of OSSD processes. Finally, the various application scenarios of OSSD model methods - also in commercial SE - are identified and an implementation approach based on the OSS GENESIS is presented which can be used to implement and support the OSSD model.