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An intelligent assistant to re-configure parameter-driven systemsPoon, Josiah Chun-Fai, josiah.poon@deakin.edu.au January 1994 (has links)
Parameter-Driven Systems (PDS) are widely used in commerce for large-scale applications. Reusability is achieved with a PDS design by relocating implicit control structures in the software and the storage of explicit data in database files.
This approach can accommodate various user requirements without tedious modification of the software. In order to specify appropriate parameters in a system, knowledge of both business activities and system behaviour are required. For large, complex software packages, this task becomes time consuming and requires specialist knowledge, yet the consistency and correctness still cannot be guaranteed.
My research studied the types of knowledge required and agents involved in the PDS customisation. The work also identified the associated problems and constraints. A solution is proposed and implemented as an Intelligent Assistant prototype than a manual approach.
Three areas of achievement have been highlighted: 1. The characteristics and problems of maintaining parameter instances in a PDS are defined. It is found that the verification is not complete with the technical/structural knowledge alone, but a context is necessary to provide semantic information and related business activities (thus the implemented parameters) so that mainline functions can relate with each other. 2. A knowledge-based modelling approach has been proposed and demonstrated via a practical implementation. A Specification Language was designed which can model various types of knowledge in a PDS and encapsulate relationships. The Knowledge-Based System (KBS) developed verifies parameters based on the interpreted model of a given context. 3. The performance of the Intelligent Assistant prototype was well received by the domain specialist from the participating organisation. The modelling and KBS approach developed in my research offers considerable promise in solving practical problems in the software industry.
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The implications of actinide generation and destruction in accelerator driven sub-critical reactorsCoates, David John January 2012 (has links)
No description available.
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Phase transitions in low-dimensional driven systemsCosta, Andre January 2012 (has links)
The study of non-equilibrium physics is an area of interest since, unlike for their equilibrium counterparts, there exists no general framework for solving such systems. In this thesis I investigate the emergence of structure and front propagation in driven systems, a special type of system within the area of non-equilibrium physics. In particular I focus on three particular one-dimensional models each of which illustrate this in a different way. The Driven Asymmetric Contact Process (DACP) describes a system where activity is continuously generated at one end of a one-dimensional lattice and where this activity is allowed to spread in one direction along the lattice. In the DACP one observes a propagating wave of activity which appears to abruptly vanish as the system undergoes a phase transition. Using a modified Fisher equation to model the system reveals the continued existence of the propagating wave, now contained within a decaying envelope. Furthermore this establishes relations between properties of the travelling wave and Directed Percolation critical exponents. The Zero-Range Process (ZRP) is a much studied system exhibiting a condensation transition. In the ZRP individual particles hop along a lattice at rates which depend only on the occupancy of the departure site. Here I investigate a modi cation of the ZRP where instead the majority of the particles at a site depart during a single hopping event. For this, the Chipping model, a condensate which propagates along the lattice is observed. It is found that this condensation transition is present even for hop rates which fall foul of the condensation requirements of the normal ZRP. Further it is observed that, unlike for normal ZRP, condensation occurs even in the low-density limit. As a result I suggest a condensation mechanism which depends only on the hop rates of low occupancy sites. The Host-Solute-Vacancy model (HSV) is a three-species system designed to model electromigration in a circuit. As the parameter space is navigated the system undergoes what appear to be two separate phase transitions from a randomly distributed state to a condensed state with either of two structures. To investigate the model new measures for determining condensation are developed. These show that, again, condensation occurs in the low-density limit. By a reduction to a ZRP an effective hop rate of the system is measured. This effective hop rate is found to beta function of the occupancy of a site as a fraction of the total system size. To explain this behaviour I invoke a description whereby there is a step in the hop rate as a function of occupancy. Through these three examples I illustrate how minor modi cations to the dynamics of known systems can result in a new and rich phenomenology. I draw particular attention to the effect of asymmetry in the dynamics.
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Formation and Ripening of Nanobelts/Nanofibers under Stirring of aqueous Solution – alternative modelsKorol, Yaroslav, Gusak, Andriy, Danielewski, Marek, Gajewska, Marta 21 September 2022 (has links)
Problem of V2 O5 nanobelts production under intensive stirring of V2 O5 powder in salted
water is revisited. Method was initially proposed in 2016 but models and understanding were
lacking. Here an independent attempt of the controlled V2 O5 nanobelts formation and growth
under stirring with various rotation frequencies is reported, as well as some alternative
mechanisms and respective mathematical models of the nanobelts growth and ripening
kinetics.
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DESCRIPTION AND ANALYSIS OF A FLEXIBLE HARDWARE ARCHITECTURE FOR EVENT-DRIVEN DISTRIBUTED SENSOR NETWORK NODESDavis, Jesse, Kyker, Ron, Berry, Nina 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A particular engineering aspect of distributed sensor networks that has not received
adequate attention is the system level hardware architecture of the individual nodes of the
network. A novel hardware architecture based on an idea of task specific modular
computing is proposed to provide for both the high flexibility and low power
consumption required for distributed sensing solutions. The power consumption of the
architecture is mathematically analyzed against a traditional approach, and guidelines are
developed for application scenarios that would benefit from using this new design.
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Dynamics of repeatedly driven closed systemsD'Alessio, Luca 07 April 2016 (has links)
This thesis covers my work in the field of closed, repeatedly
driven, Hamiltonian systems. These systems do not exchange
particles with the surrounding environment and their time-evolution
is described by Hamilton's equations of motion (in the classical
framework) or the Schroedinger equation (in the quantum framework).
Their interaction with the environment is encoded into the time-dependence of the system's Hamiltonian.
Chapter 1 is an "Overview" in which the status of the field,
my contributions and future prospective are outlined.
Chapters 2 to 4 provide the theoretical background which
is used in Chapters 5 to 7 to derive some original results.
These results show that in Hamiltonian systems,
after many driving events, universal properties emerge.
In particular, using the framework of the linear Boltzmann equation, I have studied the dynamics of a mobile, light impurity in a gas of heavy particles.
The impurity's kinetic energy increases and, in the long time limit,
approaches a non-thermal asymptotic distribution.
The significance of this work is to show explicitly
the emergence of a non-thermal distribution in a closed, driven system.
Moreover, using the work-fluctuation theorems, I have studied the character of the energy distribution of a generic isolated system driven according a generic protocol. Both thermal and non-thermal distributions can be realized for the same system by changing the characteristics of the driving protocol. These two different regimes are separated by a dynamical phase transition.
Finally, I have used the Floquet Theory and the
Magnus Expansion to analyze the behavior of a generic interacting system
which is driven periodically in time.
For fast driving the system is unable to absorb
energy and remains localized in the low energy part of the Hilbert space while for slow
driving the system absorbs energy and, in the long time limit, it is delocalized
in the entire Hilbert space. These two qualitatively different behaviors are separated by a
many-body localization transition which is related to the break down of the Magnus
expansion at the critical value of the driving frequency.
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Improvement of belt tension monitoring in a belt-driven automated material handling systemMusselman, Marcus William 23 December 2010 (has links)
The goal of the study presented in this thesis was the improvement of estimation and monitoring procedures for condition monitoring of belt tension and misalignment in belt-driven automated material handling systems widely used in modern semiconductor manufacturing systems. In pursuit of this goal, two 3-factor, 3-level experiments were designed to study how belt vibration characteristics depend on changes in belt length, belt tension, belt misalignment, and initial location of the excitation of belt vibration. Dependent variables in each of the experiments were drawn from a denoised frequency spectrum calculated from an Autoregressive model of the belt vibration time-series. A feature vector was developed from the Autoregressive features via variance based sensitivity analysis. Results showed that belt vibration characteristics were sensitive to changes in all of the independent variables examined. These results motivated the design of a device to improve the standardized technique widely used to monitor belt tension in belt-driven material handling systems. Reducing variance in the belt length and the location of the initial excitation of belt vibration yielded a reduction of tension estimate standard deviation an order of magnitude, as compared to a human performing the standardized technique. Thus, the use of this device provided higher belt tension estimate resolution. Future work that could lead to a less intrusive technique is presented. / text
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Modelagem de sistemas de controle distribuídos e colaborativos de sistemas produtivos. / Modeling of distributed collaborative control systems of production systems.Matsusaki, Cristina Toshie Motohashi 27 October 2004 (has links)
O rápido avanço tecnológico nestes últimos anos, principalmente dos recursos computacionais e de comunicação, permite que os sistemas produtivos (SP) evoluam tanto no seu aspecto estrutural quanto no comportamental para que atendam às necessidades crescentes do mercado. Os elementos integrantes dos SP vêm incorporando estes avanços, atingindo maior autonomia e flexibilidade p ara cumprir suas funcionalidades. Além disso, a tendência dos dispositivos de controle de incorporar a capacidade de atuação em ambientes distribuídos onde a interação ocorre através de redes de comunicação, verificada na evolução das normas aplicadas a sistemas de controle, reflete a necessidade de aderência dos sistemas de controle a essa realidade. A necessidade de se manter competitivo no mercado impõe aos atuais SP situações em que emergem novos desafios para realização do controle dos seus processos globais, uma vez que estes assumem múltiplos objetivos, envolvendo diferentes naturezas de indeterminismo, assincronismo e variância no tempo, provocando um nível de complexidade inédito no que se refere ao controle destes sistemas. Este trabalho propõe inicialmente uma nova abstração para modelar-se os SP baseada no conceito de decomposição multidimensional e em múltiplas faces, distribuindo o controle através dos componentes colaborativos. Feito isto, são propostos procedimentos e técnicas para modelagem de sistemas de controle distribuídos e colaborativos (SCDC) de SP. Considera-se para isso, primeiro, uma arquitetura lógica de controle que contemple os múltiplos domínios semânticos presentes em SP, que são provenientes das especificidades dos elementos integrantes. Segundo, a multiplicidade de habilidades necessárias para garantir a execução das estratégias de controle pertinentes a cada domínio. Terceiro, o fluxo de informações heterogêneas provenientes das interações colaborativas entre os domínios. / Recent technological advances, mainly of computer and communication systems, allow the production systems (SP) to evolve in structural aspect as well as in behavioral aspect. The SP resources have achieved enhanced autonomy and flexibility with embedded computer and communication capability. Latest trends of control devices, as seen in the evolution of standards related to control systems, focus on the use of these devices in a distributed environment, where interaction occur through a communication network Thus, the SP control system and its design methods have to fit to this reality. In a competitive scenario, the SP are challenged to keep control of the global processes, considering the multiple goals of these processes and the involvement of different aspect of indeterminism, lack of synchronisms and time variance, generating a inedited complexity level for control of this systems. This work proposes a new abstraction for modeling the control systems of SP, based on the concept of multidimensional decompositions. Based on this, it introduces the procedures and techniques for modeling the distributed and collaborative control systems (SCDC) of the production systems. First, it considers the logic architecture of the control that support many semantic domains presented in this type of SP. Then, the diversity of skills related to each domain necessary to accomplish the control strategies. And then, the heterogeneous information flow through the domains boundaries, derived from the collaborative interaction between the control components.
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Modelagem de sistemas de controle distribuídos e colaborativos de sistemas produtivos. / Modeling of distributed collaborative control systems of production systems.Cristina Toshie Motohashi Matsusaki 27 October 2004 (has links)
O rápido avanço tecnológico nestes últimos anos, principalmente dos recursos computacionais e de comunicação, permite que os sistemas produtivos (SP) evoluam tanto no seu aspecto estrutural quanto no comportamental para que atendam às necessidades crescentes do mercado. Os elementos integrantes dos SP vêm incorporando estes avanços, atingindo maior autonomia e flexibilidade p ara cumprir suas funcionalidades. Além disso, a tendência dos dispositivos de controle de incorporar a capacidade de atuação em ambientes distribuídos onde a interação ocorre através de redes de comunicação, verificada na evolução das normas aplicadas a sistemas de controle, reflete a necessidade de aderência dos sistemas de controle a essa realidade. A necessidade de se manter competitivo no mercado impõe aos atuais SP situações em que emergem novos desafios para realização do controle dos seus processos globais, uma vez que estes assumem múltiplos objetivos, envolvendo diferentes naturezas de indeterminismo, assincronismo e variância no tempo, provocando um nível de complexidade inédito no que se refere ao controle destes sistemas. Este trabalho propõe inicialmente uma nova abstração para modelar-se os SP baseada no conceito de decomposição multidimensional e em múltiplas faces, distribuindo o controle através dos componentes colaborativos. Feito isto, são propostos procedimentos e técnicas para modelagem de sistemas de controle distribuídos e colaborativos (SCDC) de SP. Considera-se para isso, primeiro, uma arquitetura lógica de controle que contemple os múltiplos domínios semânticos presentes em SP, que são provenientes das especificidades dos elementos integrantes. Segundo, a multiplicidade de habilidades necessárias para garantir a execução das estratégias de controle pertinentes a cada domínio. Terceiro, o fluxo de informações heterogêneas provenientes das interações colaborativas entre os domínios. / Recent technological advances, mainly of computer and communication systems, allow the production systems (SP) to evolve in structural aspect as well as in behavioral aspect. The SP resources have achieved enhanced autonomy and flexibility with embedded computer and communication capability. Latest trends of control devices, as seen in the evolution of standards related to control systems, focus on the use of these devices in a distributed environment, where interaction occur through a communication network Thus, the SP control system and its design methods have to fit to this reality. In a competitive scenario, the SP are challenged to keep control of the global processes, considering the multiple goals of these processes and the involvement of different aspect of indeterminism, lack of synchronisms and time variance, generating a inedited complexity level for control of this systems. This work proposes a new abstraction for modeling the control systems of SP, based on the concept of multidimensional decompositions. Based on this, it introduces the procedures and techniques for modeling the distributed and collaborative control systems (SCDC) of the production systems. First, it considers the logic architecture of the control that support many semantic domains presented in this type of SP. Then, the diversity of skills related to each domain necessary to accomplish the control strategies. And then, the heterogeneous information flow through the domains boundaries, derived from the collaborative interaction between the control components.
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Neutron induced light-ion production from iron and bismuth at 175 MeVBevilacqua, Riccardo January 2010 (has links)
<p>Light-ions (protons, deuterons, tritons, <sup>3</sup>He and α articles) production in the interaction of 175 MeV neutrons with iron and bismuth has been measured using the Medley setup at the The Svedberg Laboratory (TSL) in Uppsala. These measurements have been conducted in the frame of an international collaboration whose aim is to provide the scientific community with new nuclear data of interest for the development of Accelerator Driven Systems, in the range of 20 to 200 MeV. In this Licentiate Thesis I will present the background for the present experiment, the choice of the measured materials (iron and bismuth) and of the energy range. I will then give a short theoretical description of the involved nuclear reactions and of the model used to compare the experimental results. A description of the neutron facility at TSL and of Medley setup will follow. Monte Carlo simulations of the experimental setup have been performed and some results are here reported and discussed. I will present data reduction procedure and finally I will report preliminary double differential cross sections for production of hydrogen isotopes from iron and bismuth at several emission angles. Experimental data will be compared with model calculations with TALYS-1.0; these show better agreement for the production of protons, while seems to overestimate the experimental production of deuterons and tritons.</p>
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