Checkpointing is a technique widely used in parallel/distributed computers for rollback error recovery. Checkpointing is defined as the coordinated saving of process state information at specified time instances. Checkpoints help in restoring the computation from the latest saved state, in case of failure. In addition to fault recovery, checkpointing has applications in fault detection, distributed debugging and process migration. Checkpointing in uniprocessor systems is easy due to the fact that there is a single clock and events occur with respect to this clock. There is a clear demarcation of events that happens before a checkpoint and events that happens after a checkpoint. In parallel computers a large number of computers coordinate to solve a single problem. Since there might be multiple streams of execution, checkpoints have to be introduced along all these streams simultaneously. Absence of a global clock necessitates explicit coordination to obtain a consistent global state. Events occurring in a distributed system, can be ordered partially using Lamport's happens before relation. Lamport's happens before relation ->is a partial ordering relation to identify dependent and concurrent events occurring in a distributed system. It is defined as follows: ·If two events a and b happen in the same process, and if a happens before b, then a->b ·If a is the sending event of a message and b is the receiving event of the same message then a -> b ·If neither a à b nor b -> a, then a and b are said to be concurrent. A consistent global state may have concurrent checkpoints. In the first chapter of the thesis we discuss issues regarding ordering of events in a parallel computer, need for coordination among checkpoints and other aspects related to checkpointing. Checkpointing locations can either be identified statically or dynamically. The static approach assumes that a representation of a program to be checkpointed is available with information that enables a programmer to specify the places where checkpoints are to be taken. The dynamic approach identifies the checkpointing locations at run time. In this thesis, we have proposed algorithms for both static and dynamic checkpointing. The main contributions of this thesis are as follows: 1. Parallel computers that are being built now have faster communication and hence more efficient clock synchronisation compared to those built a few years ago. Based on efficient clock synchronisation protocols, the clock drift in current machines can be maintained within a few microseconds. We have proposed a dynamic checkpointing algorithm for parallel computers assuming bounded clock drifts. 2. The shared memory paradigm is convenient for programming while message passing paradigm is easy to scale. Distributed Shared Memory (DSM) systems combine the advantage of both paradigms and can be visualized easily on top of a network of workstations. IEEE has recently proposed an interconnect standard called Scalable Coherent Interface (SCI), to con6gure computers as a Distributed Shared Memory system. A periodic dynamic checkpointing algorithm has been proposed in the thesis for a DSM system which uses the SCI standard. 3. When information about a parallel program is available one can make use of this knowledge to perform efficient checkpointing. A static checkpointing approach based on task graphs is proposed for parallel programs. The proposed task graph based static checkpointing approach has been implemented on a Parallel Virtual Machine (PVM) platform. We now give a gist of various chapters of the thesis. Chapter 2 of the thesis gives a classification of existing checkpointing algorithms. The chapter surveys algorithm that have been reported in literature for checkpointing parallel/distributed systems. A point to be noted is that most of the algorithms published for checkpointing message passing systems are based on the seminal article by Chandy & Lamport. A large number of checkpointing algorithms have been published by relaxing the assumptions made in the above mentioned article and by extending the features to minimise the overheads of coordination and context saving. Checkpointing for shared memory systems primarily extend cache coherence protocols to maintain a consistent memory. All of them assume that the main memory is safe for storing the context. Recently algorithms have been published for distributed shared memory systems, which extend the cache coherence protocols used in shared memory systems. They however also include methods for storing the status of distributed memory in stable storage. Chapter 2 concludes with brief comments on the desirable features of a checkpointing algorithm. In Chapter 3, we develop a dynamic checkpointing algorithm for message passing systems assuming that the clock drift of processors in the system is bounded. Efficient clock synchronisation protocols have been implemented on recent parallel computers owing to the fact that communication between processors is very fast. Based on efficient clock synchronisation protocols, clock skew can be limited to a few microseconds. The algorithm proposed in the thesis uses clocks for checkpoint coordination and vector counts for identifying messages to be logged. The algorithm is a periodic, distributed algorithm. We prove correctness of the algorithm and compare it with similar clock based algorithms. Distributed Shared Memory (DSM) systems provide the benefit of ease of programming in a scalable system. The recently proposed IEEE Scalable Coherent Interface (SCI) standard, facilitates the construction of scalable coherent systems. In Chapter 4 we discuss a checkpointing algorithm for an SCI based DSM system. SCI maintains cache coherence in hardware using a distributed cache directory which scales with the number of processors in the system. SCI recommends a two phase transaction protocol for communication. Our algorithm is a two phase centralised coordinated algorithm. Phase one initiates checkpoints and the checkpointing activity is completed in phase two. The correctness of the algorithm is established theoretically. The chapter concludes with the discussion of the features of SCI exploited by the checkpointing algorithm proposed in the thesis. In Chapter 5, a static checkpointing algorithm is developed assuming that the program to be executed on a parallel computer is given as a directed acyclic task graph. We assume that the estimates of the time to execute each task in the task graph is given. Given the timing at which checkpoints are to be taken, the algorithm identifies a set of edges where checkpointing tasks can be placed ensuring that they form a consistent global checkpoint. The proposed algorithm eliminates coordination overhead at run time. It significantly reduces the context saving overhead by taking checkpoints along edges of the task graph. The algorithm is used as a preprocessing step before scheduling the tasks to processors. The algorithm complexity is O(km) where m is the number of edges in the graph and k the maximum number of global checkpoints to be taken. The static algorithm is implemented on a parallel computer with a PVM environment as it is widely available and portable. The task graph of a program can be constructed manually or through program development tools. Our implementation is a collection of preprocessing and run time routines. The preprocessing routines operate on the task graph information to generate a set of edges to be checkpointed for each global checkpoint and write the information on disk. The run time routines save the context along the marked edges. In case of recovery, the recovery algorithms read the information from stable storage and reconstruct the context. The limitation of our static checkpointing algorithm is that it can operate only on deterministic task graphs. To demonstrate the practical feasibility of the proposed approach, case studies of checkpointing some parallel programs are included in the thesis. We conclude the thesis with a summary of proposed algorithms and possible directions to continue research in the area of checkpointing.

This study investigated a series of independent unassisted and device-assisted transfers from a wheelchair to vehicle mock-up and vice versa while simultaneously capturing kinematic, kinetic and electromyographic (EMG) data of impaired volunteers. The study provides a venue for observation and evaluation of upper extremity (UE) joint stresses, muscular force and functional demands associated with transfers in persons with spinal cord injury (SCI) to ultimately prevent UE injury, minimize excessive stress, preserve functionality and limit pain. If people with SCI lose function of their UEs, due to pain and/or degeneration, they must then rely on others for everyday tasks. Five paraplegic males from the Tampa Bay area were recruited to take part in the study. Participants were asked to perform a series of transfers using 4 commercially available devices or mock-ups of that device as well as an unassisted transfer, which permitted the use of no assistive device. Three data types were captured: kinematic data using motion capture, kinetic data using force transducers which were integrated into the vehicle mock-up and EMG of 5 bilateral muscle groups. Data collection took approximately 4 hours per subject. Forces occurring during the unassisted transfers were found to be the highest. This is also supported by the EMG data. Performing level transfers lessened stresses at the UE versus non-level transfers. The highest moments of the UEs were found at the shoulders with high variability between subjects. It was also found that body mass index (BMI) had an affect on a subjects ability to perform transfers. Ultimately this study found that using an assistive device is better than not using an assistive device. This is proven by EMG and force data, which were both found to be less with the use of an assistive device as opposed to transferring independently with no assistance. Performing level transfers, maintaining ones body mass and staying active are all factors that will limit stresses at the UEs during wheelchair transfers to and from a vehicle.

Spasticity is highly prevalent in neurological conditions involving upper motor neuron lesions (UMNL). Lower limb spasticity is known to impair gait and limit participation in physical activity. Multimodal interventions including botulinum toxin A, orthoses, and physiotherapy have shown longer lasting improvements compared to unimodal interventions. Studies to date, however, have not examined the long term efficacy of this multimodal intervention nor have they examined the impact across a breadth of domains necessary to comprehensively and fully understand its impact. The aim of this study was to investigate the efficacy of a multimodal intervention to treat lower limb spasticity in adults using a longitudinal mixed-methods approach, including a comprehensive set of outcome measures spanning the domains of the International Classification of Functioning, Disability and Health (ICF) model. Seven-teen participants with chronic UMNL were included in the analysis as per inclusion criteria and showed improvements at 6 and 12 months, compared to baseline, within all domains of the ICF model. / Graduate / 0571 / 0382 / 0384 / jazkim@uvic.ca

Spasticity is highly prevalent in neurological conditions involving upper motor neuron lesions (UMNL). Lower limb spasticity is known to impair gait and limit participation in physical activity. Multimodal interventions including botulinum toxin A, orthoses, and physiotherapy have shown longer lasting improvements compared to unimodal interventions. Studies to date, however, have not examined the long term efficacy of this multimodal intervention nor have they examined the impact across a breadth of domains necessary to comprehensively and fully understand its impact. The aim of this study was to investigate the efficacy of a multimodal intervention to treat lower limb spasticity in adults using a longitudinal mixed-methods approach, including a comprehensive set of outcome measures spanning the domains of the International Classification of Functioning, Disability and Health (ICF) model. Seven-teen participants with chronic UMNL were included in the analysis as per inclusion criteria and showed improvements at 6 and 12 months, compared to baseline, within all domains of the ICF model. / Graduate / 2015-04-24 / 0571 / 0382 / 0384 / jazkim@uvic.ca

Feminist Science Fiction: Cherie Priest's The Clockwork Century Diploma Thesis Petra Nováková Abstract Marleen S. Barr, one of the pioneers of feminist science fiction criticism, is an outspoken commentator on gender inequality in this genre. In Feminist Fabulation: Space/Postmodern Fiction and Future Females: A Critical Anthology, Barr defines feminist science fiction as metafiction about patriarchal fiction. She speaks out against both authors and critics who recycle narratives restricted by a patriarchal view of the world in which women are silenced and/or relegated to the position of an accessory of the male hero, made to behave in a stereotypically feminine manner. While Barr does not include steampunk fiction but focuses on science fiction oriented towards the future and space exploration, her analysis of the female character's plight is nonetheless applicable to the steampunk genre. In this respect, feminist steampunk fiction can be read as a meditation on established gender norms. Cherie Priest's work is a prime example of such an innovative re-examination of gender stereotypes that Barr calls for in her critical work. As both a woman and a writer of science fiction, the author has adopted a feminist approach in her steampunk series The Clockwork Century. Among other things, Priest examines the role...

The study purposes were to identify changes in resilience, satisfaction with life (SWL), depression, spirituality, and functional independence (FI) and to examine the relationship between these variables, during the inpatient rehabilitation for a spinal cord injury (SCI). The sample included 42 individuals with a SCI, 33 males and 9 females, who were inpatients with a mean stay of 52 days (SD = 15.78). A repeated measures design was employed with questionnaires completed at three times during rehabilitation. Results indicated that there were significant changes in depression, satisfaction with life, spirituality, and FI during inpatient rehabilitation. Findings also indicated significant correlations between resilience, SWL, spirituality, and depression. Future studies developing interventions, and examining factors that predict resilience could help build resilience and may improve rehabilitation outcomes.

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Sowohl auf nationaler als auch internationaler Ebene sind bei elektronischen Stellwerken der ersten Generation die Schnittstellen zwischen den Bestandteilen der Leit- und Sicherungstechnik (LST) überwiegend herstellerspezifisch gestaltet. Das EULYNX-Konsortium befasst sich in Europa aus diesem Grund mit der Spezifizierung von standardisierten Schnittstellen im Bereich der LST. Die wesentlichen Ziele, welche es unter der Nutzung von konventioneller Netzwerktechnik und durch eine Entkopplung der Anlagenbestandteile zu erreichen gilt, sind das Fördern des Wettbewerbs zwischen der Signalbauindustrie, das Reduzieren der Lebenszykluskosten und das Verhindern der Obsoleszenz. Die Professur für Verkehrssicherungstechnik strebt für eine aktive Beteiligung an der Weiterentwicklung von standardisierten Schnittstellen den Aufbau von EULYNX-Versuchsständen an. Dazu betrachtet diese Masterarbeit die Hochrüstung der im Sicherungstechnischen Labor vorhandenen Bahnübergangssicherungsanlage (BÜSA) BUES 2000 auf eine EULYNX-Schnittstelle und analysiert verschiedene Varianten zur Gestaltung einer umgebenden Laboranlage sowie eines Versuchsstandes. Ein weiterer Forschungsgegenstand ist dabei die Recherche der erforderlichen Voraussetzungen zur Nutzung der konzipierten Laboranlage für Validierungsaufgaben. Den Abschluss dieser Ausarbeitung bildet ein Testkonzept, welches in der Form von Testspezifikationen sowohl für die Integration als auch die Validierung des Versuchsstandes verwendet werden kann.

Die vorliegende Diplomarbeit befasst sich mit modernen Überwachungsarten für die Einbindung von Bahnübergängen auf ETCS-Strecken. Im Rahmen der Harmonisierung des europäischen Eisenbahnverkehrs werden Strecken zunehmend mit dem Zugbeeinflussungssystem ETCS ausgerüstet, wobei vollüberwachte Systeme eine bedeutende Rolle spielen. Durch flache ETCS-Bremskurven kann es an Bahnübergängen herkömmlicher Überwachungsarten zu betrieblichen Einschränkungen kommen, was es zu vermeiden gilt. Ziel dieser Diplomarbeit ist es, Potenziale moderner Überwachungsarten für Bahnübergänge auf ETCS-Strecken aufzuzeigen. Zu Beginn werden herkömmliche Überwachungsarten und Konflikte bei deren Einbindung auf ETCS-Strecken beleuchtet. Es folgt eine Untersuchung der modernen Überwachungsarten sowie der zukünftigen Schnittstellenarchitektur zwischen Bahnübergangssicherungsanlage (BÜSA) und Stellwerk. Darauf aufbauend werden Vergleiche mit konventionellen Überwachungsarten anhand von beispielhaften Anwendungsfällen angestellt und Möglichkeiten zur Beschleunigung des Entwicklungsprozesses für eine zeitnahe Anwendungsreife identifiziert. Abschließend erfolgt eine Prüfung der Voraussetzungen für die Erprobung im Sicherungstechnischen Labor der TU Dresden.:1 Einführung 2 Grundlagen 3 Moderne Überwachungsarten Bahnübergänge 4 Moderne Überwachungsarten auf ETCS-Strecken 5 Entwicklung der Standardschnittstelle SCI-LX 6 Erprobung im SIL 7 Ergebnisse und Diskussion 8 Zusammenfassung und Ausblick / The present study addresses modern types of level crossing monitoring for the integration of level crossings on ETCS railway lines. As part of the harmonization of European rail traffic, lines are increasingly being equipped with the European Train Control System (ETCS), whereby fully supervised systems play an important role. Due to flat ETCS braking curves, operational restrictions can occur at level crossings of conventional monitoring types, which must be avoided. The aim of this study is to highlight the potential of modern level crossing monitoring types on ETCS lines and to identify outstanding development steps up to application maturity. At the beginning, conventional types of level crossing monitoring and conflicts in their integration on ETCS lines are examined. This is followed by an analyzation of new level crossing monitoring types and the future interface architecture between the level crossing protection system and the interlocking. Based on this, comparisons are made with conventional monitoring types by use cases, and possibilities for accelerating steps in the development process for timely application maturity are identified. Finally, the prerequisites for testing in the Railway Safety Engineering Laboratory of the TU Dresden are checked.:1 Einführung 2 Grundlagen 3 Moderne Überwachungsarten Bahnübergänge 4 Moderne Überwachungsarten auf ETCS-Strecken 5 Entwicklung der Standardschnittstelle SCI-LX 6 Erprobung im SIL 7 Ergebnisse und Diskussion 8 Zusammenfassung und Ausblick

Background: Alterations of hypothalamic–pituitary–adrenal (HPA) axis activity and serotonergic signaling are implicated in the pathogenesis of human obesity and may contribute to its metabolic and mental complications. The association of these systems has not been investigated in human obesity. Objective: To investigate the relation of HPA responsiveness and serotonin transporter (5-HTT) availability in otherwise healthy individuals with obesity class II or III (OB) compared to non-obesity controls (NO). Study participants: Twenty-eight OB (21 females; age 36.6 10.6 years; body mass index (BMI) 41.2 5.1 kg/m2) were compared to 12 healthy NO (8 females; age 35.8 7.4 years; BMI 22.4 2.3 kg/m2), matched for age and sex. Methods: HPA axis responsiveness was investigated using the combined dexamethasone/corticotropin-releasing hormone (dex/CRH) test, and curve indicators were derived for cortisol and adrenocorticotropic hormone (ACTH). The 5-HTT selective tracer [11C]DASB was applied, and parametric images of the binding potentials (BPND) were calculated using the multilinear reference tissue model and evaluated by atlas-based volume of interest (VOI) analysis. The self-questionnaires of behavioral inhibition system/behavioral activation system (BIS/BAS) with subscales drive, fun-seeking and reward were assessed. Results: OB showed significant positive correlations of ACTH curve parameters with overall 5-HTT BPND (ACTHAUC: r = 0.39, p = 0.04) and 5-HTT BPND of the caudate nucleus (ACTHAUC: r = 0.54, p = 0.003). In NO, cortisol indicators correlated significantly with BPND in the hippocampus (cortisolAUC: r = 0.59, p = 0.04). In OB, BAS reward was inversely associated with the ACTHAUC (r = 0.49, p = 0.009). Conclusion: The present study supports a serotonergic-neuroendocrine association, which regionally differs between OB and NO. In OB, areas processing emotion and reward seem to be in-volved. The finding of a serotonergic HPA correlation may have implications for other diseases with dysregulated stress axis responsiveness, and for potential pharmacologic interven-tions.