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Produzierende Unternehmen sehen sich einem stetig wachsenden Kostendruck ausgesetzt, der durch steigende Rohstoffpreise zusätzlich verschärft wird. In diesem Umfeld wächst die Notwendigkeit einer möglichst fehlerfreien Produktion. Eine vollständige Vermeidung von Fehlern und Ausfällen durch konstruktive Maßnahmen sowie durch die Berücksichtigung von Sicherheiten ist während des Entwurfs nicht mit akzeptablem Aufwand zu verwirklichen. Eine Möglichkeit, die Prozesssicherheit dennoch weiter zu steigern, ist die Überwachung von Prozess‐ und Maschinenparametern. Obwohl geregelte Antriebe eine zentrale Position in der industriellen Fertigung einnehmen, spielen diese bei der Überwachung bisher in Wissenschaft und Praxis kaum eine Rolle. Der durch die Antriebsregelung wesentlich beeinflusste Punkt der Dynamik und die Regelkreise selbst werden nicht oder nur ungenügend in die Überwachung einbezogen. Aus folgenden Trends in der Produktionstechnik lässt sich jedoch ein steigender Einfluss der Antriebsregelkreise auf das gesamte Maschinenverhalten ableiten: - Durch den Einsatz von Direktantrieben entfallen mechanische Übertragungsglieder und deren Filterwirkung. Somit wirken einerseits die Prozessgrößen unmittelbarer auf Antriebsgrößen und zum anderen steigt der Einfluss des Regelverhaltens auf den Prozess. - Durch Leichtbau und Reduzierung der Reibung werden die dämpfenden Eigenschaften der Mechanik reduziert. - Leichtere, flexiblere Strukturen mit sinkender Dämpfung stellen hohe Ansprüche an die eingesetzten Regler. Unter Umständen werden arbeitspunktabhängige Reglereinstellungen oder die Adaption der Reglerparameter notwendig. Ein zeitgemäßes Maschinenmonitoring erfordert daher die Einbeziehung des Reglerverhaltens in die Überwachungsstrategie. Voraussetzung dafür sind auf die Anforderungen der Antriebsregelung zugeschnittene Methoden. Als zentraler Regelkreis besitzt die Drehzahl bzw. Geschwindigkeitsregelung großen Einfluss auf die Dynamik der Lageregelung. Typischerweise wird für den geschlossenen Drehzahlregler eine möglichst große Bandbreite bei einer Dämpfung von 0,5 ‐ 0,7 angestrebt. Die beschriebene Herangehensweise überwacht die Güte der Drehzahlregelung anhand deren Dämpfungsverhaltens und detektiert insbesondere aggressive, zu Schwingungen neigende Parametrierungen (D<0,3). Zu diesem Zweck wird die Regelabweichung der Geschwindigkeit mithilfe der Prony‐Methode analysiert. Es werden Vorteile der beschriebenen Methode dargestellt und potentielle Anwendungsgebiete aufgezeigt. Zudem wird kurz die prototypische Umsetzung auf Standardsteuerungshardware und Untersuchungen an verschiedenen Versuchsständen behandelt.

Currently, it is uncertain how well a typical ground-based simulator's hexapod motion system can simulate the aggressive motion during airplane upset. To address this issue, this thesis attempts to improve simulator motion for upset recovery simulation by defining new motion fidelity criteria, implementing body frame filtering, and improving an existing adaptive motion drive algorithm. The successfully improved adaptive algorithm was used to conduct a paired comparison experiment to study the effects of trade-offs between translational and rotational motion cues on pilot subjective fidelity and upset recovery performance. Analysis of the experimental data found that pilots generally rejected motion with false lateral cues and they preferred the presence of rotational cues for moderate roll angles. Also, performance analysis suggested that roll cues helped improve lateral control. Overall, pilots preferred to have simulator motion during upset simulation and significant improvements in performance were observed when simulator motion was present.

IEEE 802.11 PHY supports multiple transmission rates according to multiple different modulations and coding schemes. Each WiFi station selects its own transmission rate according to its own algorithm; in particular, the IEEE 802.11 standards do not specify the bit-rate selection method. Although many adaptive bit-rate selection algorithms have been proposed, there is limited research and evaluation on the performance of such algorithms for roadside networks, especially in cases with multi-vehicle roadside multi-vehicular WiFi networks. In this thesis we propose an opportunistic highest bit-rate algorithm, Opportunistic Highest Bit-Rate Multi-Vehicular WiFi Networks (OHBR-MVN), specifically for roadside multi-vehicular WiFi networks. Our proposal is based on three key characteristics of such networks: (1) vehicles will drive closer to, and eventually pass, the roadside WiFi station, experiencing a progressively better transmission environment; (2) the vast majority of data transmitted in single-vehicle drive-by downloading scenarios occurs at the maximum transmission rate; (3) vehicles that transmit at less than the maximum rate do so at the expense of those that could send more data at a higher transmission rate. We therefore believe that transmitting only at the highest possible bit-rate is the preferred algorithm for such networks. Further, this approach keeps the bit-rate selection extremely simple, avoiding the complexity and resulting problems of adaptive approaches. Through a series of experiments that compare the throughput of both fixed and adaptive bit-rate selection algorithms we show that our approach yields both higher throughput and better fairness characteristics, while being significantly simple, and thus more robust.

In this study, a three-axes PC numerical control system for industrial applications has been developed. With this system, fast and cheap prototyping of designed objects can be realized. The system consists of software and a hardware which includes an XYZ positioning table and three step motors controlling this table. A proper drive circuit for the stepper motors is utilized. The software digitizes two dimensional drawings of three dimensional objects and generates the control signals for the XYZ positioning table. The software is developed under Microsoft Studio Visual Basic 6.0 environment regardless of the OS of the PC. The parallel port of the PC has been utilized for generating the necessary control signals for the stepper motors.

High dynamic performance, which is obtained from dc motors, became achievable from induction motors with the recent advances in power semiconductors, digital signal processors and development in control techniques. By using field oriented control, torque and flux of the induction motors can be controlled independently as in dc motors. The control performance of field oriented induction motor drive greatly depends on the correct stator flux estimation. In this thesis voltage model is used for the flux estimation. Stator winding resistance is used in the voltage model. Also leakage inductance, mutual inductance and referred rotor resistance values are used in vector control calculations. Motor control algorithms use motor models, which depend on motor parameters, so motor parameters should be measured accurately. Induction motor parameters may be measured by conventional no load and locked rotor test. However, an intelligent induction motor drive should be capable of identifying motor parameters itself. In this study parameter estimation algorithms are implemented and motor parameters are calculated. Then these parameters are used and rotor flux oriented vector control is implemented. Test results are presented.

My concern in Dead Drunk is not simply the subject matter of death, it is rather with the representation of drunks in the form of fictional phantoms in The Glass Canoe and Bliss as rendering the death drive visible. Close scrutiny of the representation of the drunk in Australian fiction, as discussed in relation to The Glass Canoe, and Bliss reveals a ‘constant recurrence of the same thing’ rendered uncannily visible. On inspection, what becomes visible is recurring deaths and subsequent resurrections. For the ghostly Australian drunk there is always the possibility of resurrection, but that resurrection is usually in the form of another drink. A drink promises resurrection, but instead delivers a return or recurrence of the drunken, ghostly state. / The presence of drinking and drunks in Australian fiction can be described as a haunting, the ghostly drunks as repetition of an anachronistic past. It is the repetition of the representations of drunks as ghostly presences in Australian fiction that is telling. Utilising Sigmund Freud’s theories developed in ‘The Uncanny’ (1919) and Beyond the Pleasure Principle (1920), I propose that if the uncanny is an encounter with one’s origins and the death drive is a backward looking return to origins; the drunks are a past that is repeatedly encountered in an uncanny moment. Utilising the modalities of the uncanny in regards to The Glass Canoe reveals the guises of the drunken ghosts. Making reference to an Australian colonial past, founded on intoxicant use and abuse the dissertation suggests alcoholism as a white man’s dreaming. A discussion of Bliss links the uncanny ghosts to a registration or surfacing of the death drive. In conclusion I suggest the psychoanalytic concept of sublimation as both an explanation for and a release from the symptomatic repetition. / Floundering, the creative work, is an extract from a novel in progress. The section presented is the opening to the novel. The narrative unfolds during one day, New Year’s Eve, and involves the interactions between the two brothers Jordy and Tom, and Old Fat. Loretta, the boys’ absent mother, haunts the novel and drives the narrative. Although the creative work does not explicitly depict dead drunks as discussed in the dissertation, the theory has by necessity permeated the creative, and the creative permeated the theory, forming a chiasma – a crossing over between strands of thought.

Fault tolerant motor drives are becoming more important in safety critical applications. Although a single motor module fault tolerant drive may be sufficient in some applications, this motor drive only offers limited redundancy. This thesis investigated the dual motor module fault tolerant drive system in which two motor modules were connected electrically in phase and on a common shaft provide redundancy and to increase the reliability of the entire drive system. A general phase current mathematical model to produce the desired output torque was developed to minimize copper loss and torque ripple in the motor drive, which is applicable to both sinusoidal and trapezoidal brushless permanent magnet motor types. A detailed fault effect investigation was performed in this thesis and it is concluded that switch short-circuit fault is the most serious fault since it reduces the electromagnetic torque output significantly and generates larger torque ripple in the motor drive due to the presence of large drag torque. Three fault remedial strategies were proposed to compensate the torque loss and to reduce the torque ripple under different faulty conditions. It is concluded from the analytical results that fault remedial strategy 3 is the tradeoff algorithm in which the zero torque ripple factor can be achieved with only a modest increase in copper loss comparing with the minimum possible value. Two practical dual motor module fault tolerant brushless permanent magnet drive test arrangements with different motor structures were developed in this thesis. The computer simulation studies using the MATLAB Simulink were performed to verify the effectiveness of the proposed fault remedial strategies. The efficiency of the motor drive was predicted based on torque loss measurements and the results were verified in the simulation study. The effect of faults on the drive efficiency was investigated as well. The entire fault tolerant motor drive control system was also developed to verify the analytical and simulation results. A fault detection and identification method to detect switch open-circuit faults, switch short-circuit faults, and the winding short-circuit faults was also proposed. Its advantages are the simplicity of the implementation and reduction of the cost of the drive system. The experimental results demonstrated that the proposed fault remedial strategies can be implemented in real time motor control and are effective to compensate the torque loss and reduce the torque ripple. / Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2008

The convergence of transport, communication, computing and positioning technologies has enabled a smart car revolution. As a result, pricing of roads based on telematics technologies has gained significant attention. While there are promised benefits, systematic disclosure of precise location has the ability to impinge on privacy of a special kind, known as location privacy. The aim of this thesis is to provide technical designs that enhance the location privacy of motorists without compromising the benefits of accurate pricing. However, this research looks beyond a solely technology-based solution. For example, the ethical implications of the use of GPS data in pricing models have not been fully understood. Likewise, minimal research exists to evaluate the technical vulnerabilities that could be exploited to avoid criminal or financial penalties. To design a privacy-aware system, it is important to understand the needs of the stakeholders, most importantly the motorists. Knowledge about the anticipated privacy preferences of motorists is important in order to make reasonable predictions about their future willingness to adopt these systems. There is limited research so far on user perceptions regarding specific payment options in the uptake of privacy-aware systems. This thesis provides a critical privacy assessment of two mobility pricing systems, namely electronic tolls and mobility-priced insurance. As a result of this assessment, policy recommendations are developed which could support a common approach in facilitating privacy-aware mobility-pricing strategies. This thesis also evaluates the existing and potential inferential threats and vulnerabilities to develop security and privacy recommendations for privacy-aware pricing designs for tolls and insurance. Utilising these policy recommendations and analysing user-perception with regards to the feasibility of sustaining privacy , and willingness to pay for privacy, two privacy-aware mobility pricing designs have been presented which bridge the entire array of privacy interests and bring them together into a unified approach capable of sustaining legal protection as well as satisfying privacy requirements of motorists. It is maintained that it is only by social and technical analysis working in tandem that critical privacy issues in relation to location can be addressed.

Thesis (D. Min.)--Abilene Christian University, 1990. / Typescript. Includes bibliographical references (leaves 151-153).