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Exploring the architectures of planetary systems that form in thermally evolving viscous disc modelsColeman, Gavin Arthur Leonard January 2016 (has links)
The diversity in observed planets and planetary systems has raised the question of whether they can be explained by a single model of planet formation or whether multiple models are required. The work presented in this thesis aims to examine the oligarchic growth scenario, to determine whether the core accretion model, where planets form bottom-up, can recreate the observed diversity. I begin by exploring how changing model parameters such as disc mass and metallicity influence the types of planetary systems that emerge. I show that rapid inward migration leads to very few planets with masses mp > 10M⊕ surviving, with surviving planetary systems typically containing numerous low-mass planets. I examine what conditions are required for giant planets to form and survive migration, finding that for a planet similar to Jupiter to form and survive, it must form at an orbital radius rp > 10 au. In the second project in this thesis, I update the physical models before examining whether a broader range of parameters can produce planetary systems similar to those observed. I find that compact systems of low-mass planets form in simulations if there is sufficient solid material in the disc or if planetesimals are small, thus having increased mobility. I also find that giant planets can form when the solid abundance and mobility of planetesimals are high, however they all undergo largescale migration into the magnetospheric cavity located close to the star. For the final project of this thesis, I examined the effects that disc radial structuring has on the formation of giant planets. I find that by including radial structures, numerous giant planets are able to form at large orbital radii and survive migration. The observed period valley between 10-100 days is also recreated, of which I attribute to disc dispersal late in the disc's lifetime.
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Inverse software configuration managementMcCrindle, Rachel Jane January 1998 (has links)
Software systems are playing an increasingly important role in almost every aspect of today’s society such that they impact on our businesses, industry, leisure, health and safety. Many of these systems are extremely large and complex and depend upon the correct interaction of many hundreds or even thousands of heterogeneous components. Commensurate with this increased reliance on software is the need for high quality products that meet customer expectations, perform reliably and which can be cost-effectively and safely maintained. Techniques such as software configuration management have proved to be invaluable during the development process to ensure that this is the case. However, there are a very large number of legacy systems which were not developed under controlled conditions, but which still, need to be maintained due to the heavy investment incorporated within them. Such systems are characterised by extremely high program comprehension overheads and the probability that new errors will be introduced during the maintenance process often with serious consequences. To address the issues concerning maintenance of legacy systems this thesis has defined and developed a new process and associated maintenance model, Inverse Software Configuration Management (ISCM). This model centres on a layered approach to the program comprehension process through the definition of a number of software configuration abstractions. This information together with the set of rules for reclaiming the information is stored within an Extensible System Information Base (ESIB) via, die definition of a Programming-in-the- Environment (PITE) language, the Inverse Configuration Description Language (ICDL). In order to assist the application of the ISCM process across a wide range of software applications and system architectures, die PISCES (Proforma Identification Scheme for Configurations of Existing Systems) method has been developed as a series of defined procedures and guidelines. To underpin the method and to offer a user-friendly interface to the process a series of templates, the Proforma Increasing Complexity Series (PICS) has been developed. To enable the useful employment of these techniques on large-scale systems, the subject of automation has been addressed through the development of a flexible meta-CASE environment, the PISCES M4 (MultiMedia Maintenance Manager) system. Of particular interest within this environment is the provision of a multimedia user interface (MUI) to die maintenance process. As a means of evaluating the PISCES method and to provide feedback into die ISCM process a number of practical applications have been modelled. In summary, this research has considered a number of concepts some of which are innovative in themselves, others of which are used in an innovative manner. In combination these concepts may be considered to considerably advance the knowledge and understanding of die comprehension process during the maintenance of legacy software systems. A number of publications have already resulted from the research and several more are in preparation. Additionally a number of areas for further study have been identified some of which are already underway as funded research and development projects.
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Supporting multidisciplinary analysis using system architectures in SysMLBranscomb, Jaclyn Marie 30 May 2012 (has links)
To develop competitive vehicles with ever increasing complexity, automotive designers need to improve their ability to explore a broad range of system architectures efficiently and effectively. Whereas traditional vehicle systems are based upon internal combustion (IC) engines, today’s environmentally conscious vehicle manufacturers must consider alternatives to the IC engine-only systems such as hybrid or electric systems. To help the engineers to model these multiple alternatives, it would be ideal to start from a base vehicle architecture. To design a good vehicle, it is necessary for each of these system architectures to be analyzed from a variety of attributes including performance, fuel economy, or even thermal behavior. Creating the necessary analysis models for each system architecture would be time-consuming, expensive, and could be error prone. To aid in overcoming such challenges, we have developed an approach for supporting the generation of subsystem model templates to support the integration of analysis models. The approach is based on formally modeling the system architecture in the Systems Modeling Language (OMG SysML) and then using model transformations to generate stubs for corresponding analysis models in Modelica and Simulink. In this manner, we assist designers in managing large systems with multiple analyses, ensuring that the systems remain consistent, and enabling the reuse of generic architectures through specialization and redefinition. The starting point is a reference architecture, called the Vehicle Model Architecture or VMA, in which all the key subsystems and interactions between subsystems are formally modeled. In addition, we have created a generic template that is a specialized version of the VMA. This specialized template can then be adapted by the systems engineer to represent a specific vehicle program. In addition, pre-defined, generic analysis templates can be redefined for the specific vehicle program under analysis. The SysML VMA system model is transformed through two model transformations, one that translates the physical portion of the system to Modelica, and one that transforms the logical controls portion of the system to Simulink. By automating these transformations and reusing a set of fixed templates for further specialized architectures, this approach helps to manage the complexity, reduces modeling time by enabling system model reuse. The entire approach taken in this thesis has been named the Vehicle Architecture Modeling Framework, VAMF, which includes the SysML VMA, the corresponding analysis templates, and the tools developed to support this approach. Throughout this thesis, the specific (fictitious) vehicle program “C100” and a 0-to-100 kph performance analysis test are used as examples for demonstration.
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Architecting Smart Home Environments for Healthcare : A Database-Centric ApproachOurique de Morais, Wagner January 2015 (has links)
The development of system architectures and applications for smart homes and ambient assisted living has been the main activity of a number of academic and industrial research projects around the world. Existing system architectures for smart environments usually employ different architectural styles in a multi-layer logical architecture to support the integration and interoperation of heterogeneous hardware and software technologies, which are subsequently used to provide two major functionalities: monitoring and assistance. It is also usual among existing architectures that the database management system is the most common but the least exploited architectural component, existing in the periphery of the system and devoted exclusively for data storage and retrieval. However, database technology has advanced and matured considerably over the years, and, as a result, current database management systems can be and do more. This thesis considers the hypothesis of several features of modern database management systems being employed to address functional (e.g. well-being and security monitoring, automated control, data processing) and non-functional (e.g. interoperability, extensibility, data security and privacy) requirements of smart environments, i.e. the database management system serves as a platform for smart environments. The scope of this thesis is therefore to investigate the possibility of using different features supported by database management systems to create a database-centric system architecture for the development of smart home environments and ambient assisted living. The thesis also investigates the development of applications for health monitoring and assistance: 1) a serious game for fall prevention that assists people in practicing Tai Chi at home, and 2) a non-intrusive home-based method for sleep assessment. These features are explored in this thesis to address general functional aspects of smart environments, such as monitoring, processing, coordination and control of various types of events in a given environment. Extensibility and security features and cross-platform capabilities of database management systems are employed to accommodate non-functional, but still technical, properties of smart environments, including interoperability, extensibility, portability, scalability, security and privacy. Heterogeneous technologies are integrated into the system using programming language and platform independent software resource adapters. Interoperation among integrated technologies is mediated in an active database. The feasibility of the proposed database-centric system architecture was pragmatically investigated with the development of a "smart bedroom'' demonstrator and with the implementation of a number of short-term and long-term types of services to support active aging, aging in place and ambient assisted living. In the proposed architecture, active in-database processing maintains sensitive data within the database. This increases data security and independence from external software applications for data analysis. Changes in the system are managed during runtime, which improves flexibility and avoids system downtime. The proposed system architecture was evaluated taking into account different application scenarios and heterogeneous computing platforms. As a conclusion, modern database management systems support features that can be successfully employed in a database-centric system architecture to effectively and efficiently address functional and non-functional requirements of smart environments.
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Interdisziplinäre ProduktentwicklungEigner, Martin, Gilz, Torsten, Zafirov, Radoslav 25 September 2017 (has links) (PDF)
Aus der Einleitung:
"Innovative interdisziplinäre Produktentwicklung erfordert ein Überdenken von heutigen Methoden, Prozessen, IT-Lösungen und Organisationsformen. Insbesondere fehlt es an Unterstützung durch geeignete IT-Lösungen für die funktionale Beschreibung und Auslegung von Systemarchitekturen. Für die disziplinübergreifende Systemmodellierung der Konzeptphase gibt es nur eingeschränkte IT-Unterstützung. Elektronik und Software stellen einen immer
stärkeren Anteil im Produktentwicklungsprozess (PEP) dar. Konstruktions- und Entwurfsmethoden dieser Disziplinen sollten auf den Prüfstand gestellt und ihre Tauglichkeit für einen moderne interdisziplinären Konstruktionsansatz überprüft werden. Model Based Systems Engineering (MBSE) könnte sich als integrative Methode etablieren und eine Brücke zwischen den verschiedenen Ingenieurdisziplinen bilden. Als »Enabler« für das MBSE werden Systemmodellierungssprachen wie z.B. SysML vorgestellt, die ein Werkzeug für eine interdisziplinäre Systembeschreibung darstellen.
Auf konkreterer Stufe können Simulationssprachen, wie z.B. Matlab/Simulink oder Modelica eine frühe multidisziplinäre Simulation ermöglichen, die in Verbindung mit Systembeschreibungssprachen eine frühe Konzeptformulierung erlauben. Dieser Beitrag soll neue Methoden, Prozesse und IT-Lösungen für eine interdisziplinäre virtuelle Produktentwicklung aufzeigen (Anderl et al. 2012)."
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Interdisziplinäre ProduktentwicklungEigner, Martin, Gilz, Torsten, Zafirov, Radoslav 25 September 2017 (has links)
Aus der Einleitung:
"Innovative interdisziplinäre Produktentwicklung erfordert ein Überdenken von heutigen Methoden, Prozessen, IT-Lösungen und Organisationsformen. Insbesondere fehlt es an Unterstützung durch geeignete IT-Lösungen für die funktionale Beschreibung und Auslegung von Systemarchitekturen. Für die disziplinübergreifende Systemmodellierung der Konzeptphase gibt es nur eingeschränkte IT-Unterstützung. Elektronik und Software stellen einen immer
stärkeren Anteil im Produktentwicklungsprozess (PEP) dar. Konstruktions- und Entwurfsmethoden dieser Disziplinen sollten auf den Prüfstand gestellt und ihre Tauglichkeit für einen moderne interdisziplinären Konstruktionsansatz überprüft werden. Model Based Systems Engineering (MBSE) könnte sich als integrative Methode etablieren und eine Brücke zwischen den verschiedenen Ingenieurdisziplinen bilden. Als »Enabler« für das MBSE werden Systemmodellierungssprachen wie z.B. SysML vorgestellt, die ein Werkzeug für eine interdisziplinäre Systembeschreibung darstellen.
Auf konkreterer Stufe können Simulationssprachen, wie z.B. Matlab/Simulink oder Modelica eine frühe multidisziplinäre Simulation ermöglichen, die in Verbindung mit Systembeschreibungssprachen eine frühe Konzeptformulierung erlauben. Dieser Beitrag soll neue Methoden, Prozesse und IT-Lösungen für eine interdisziplinäre virtuelle Produktentwicklung aufzeigen (Anderl et al. 2012)."
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An analysis of LSM caching in NVRAMLersch, Lucas, Oukid, Ismail, Lehner, Wolfgang, Schreter, Ivan 13 June 2022 (has links)
The rise of NVRAM technologies promises to change the way we think about system architectures. In order to fully exploit its advantages, it is required to develop systems specially tailored for NVRAM devices. Not only this imposes great challenges, but developing full system architectures from scratch is undesirable in many scenarios due to prohibitive development costs. Instead, we analyze in this paper the behavior of an existing log-structured persistent key-value store, namely LevelDB, when run on top of an emulated NVRAM device. We investigate initial opportunities for improvement when adapting a system tailored for HDD/SSDs to run on top of an NVRAM environment. Furthermore, we analyze the behavior of the legacy DRAM caching component of LevelDB and whether more suitable caching policies are required.
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A Method for Optimised Allocation of System Architectures with Real-time ConstraintsMarcus, Ventovaara, Arman, Hasanbegović January 2018 (has links)
Optimised allocation of system architectures is a well researched area as it can greatly reduce the developmental cost of systems and increase performance and reliability in their respective applications.In conjunction with the recent shift from federated to integrated architectures in automotive, and the increasing complexity of computer systems, both in terms of software and hardware, the applications of design space exploration and optimised allocation of system architectures are of great interest.This thesis proposes a method to derive architectures and their allocations for systems with real-time constraints.The method implements integer linear programming to solve for an optimised allocation of system architectures according to a set of linear constraints while taking resource requirements, communication dependencies, and manual design choices into account.Additionally, this thesis describes and evaluates an industrial use case using the method wherein the timing characteristics of a system were evaluated, and, the method applied to simultaneously derive a system architecture, and, an optimised allocation of the system architecture.This thesis presents evidence and validations that suggest the viability of the method and its use case in an industrial setting.The work in this thesis sets precedence for future research and development, as well as future applications of the method in both industry and academia.
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Volume 3 – Conference22 June 2020 (has links)
We are pleased to present the conference proceedings for the 12th edition of the International Fluid Power Conference (IFK). The IFK is one of the world’s most significant scientific conferences on fluid power control technology and systems. It offers a common platform for the presentation and discussion of trends and innovations to manufacturers, users and scientists. The Chair of Fluid-Mechatronic Systems at the TU Dresden is organizing and hosting the IFK for the sixth time. Supporting hosts are the Fluid Power Association of the German Engineering Federation (VDMA), Dresdner Verein zur Förderung der Fluidtechnik e. V. (DVF) and GWT-TUD GmbH. The organization and the conference location alternates every two years between the Chair of Fluid-Mechatronic Systems in Dresden and the Institute for Fluid Power Drives and Systems in Aachen. The symposium on the first day is dedicated to presentations focused on methodology and fundamental research. The two following conference days offer a wide variety of application and technology orientated papers about the latest state of the art in fluid power. It is this combination that makes the IFK a unique and excellent forum for the exchange of academic research and industrial application experience. A simultaneously ongoing exhibition offers the possibility to get product information and to have individual talks with manufacturers. The theme of the 12th IFK is “Fluid Power – Future Technology”, covering topics that enable the development of 5G-ready, cost-efficient and demand-driven structures, as well as individual decentralized drives. Another topic is the real-time data exchange that allows the application of numerous predictive maintenance strategies, which will significantly increase the availability of fluid power systems and their elements and ensure their improved lifetime performance. We create an atmosphere for casual exchange by offering a vast frame and cultural program. This includes a get-together, a conference banquet, laboratory festivities and some physical activities such as jogging in Dresden’s old town.:Group 8: Pneumatics
Group 9 | 11: Mobile applications
Group 10: Special domains
Group 12: Novel system architectures
Group 13 | 15: Actuators & sensors
Group 14: Safety & reliability
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