Dissertations / Theses on the topic 'Autonomic'
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Chisnall, David. "Autonomic visualisation." Thesis, Swansea University, 2007. https://cronfa.swan.ac.uk/Record/cronfa42623.
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This thesis introduces the concept of autonomic visualisation, where principles of autonomic systems are brought to the field of visualisation infrastructure. Problems in visualisation have a specific set of requirements which are not always met by existing systems. The first half of this thesis explores a specific problem for large scale visualisation; that of data management. Visualisation algorithms have somewhat different requirements to other external memory problems, due to the fact that they often require access to all, or a large subset, of the data in a way that is highly dependent on the view. This thesis proposes a knowledge-based approach to pre-fetching in this context, and presents evidence that such an approach yields good performance. The knowledge based approach is incorporated into a five-layer model, which provides a systematic way of categorising and designing out-of-core, or external memory, systems. This model is demonstrated with two example implementations, on in the local and one in the remote context. The second half explores autonomic visualisation in the more general case. A simulation tool, created for the purpose of designing autonomic visualisation infrastructure is presented. This tool, SimEAC, provides a way of facilitating the development of techniques for managing large-scale visualisation systems. The abstract design of the simulation system, as well as details of the implementation are presented. The architecture of the simulator is explored, and then the system is evaluated in a number of case studies indicating some of the ways in which it can be used. The simulator provides a framework for experimentation and rapid prototyping of large scale autonomic systems.
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Tan, Maw Pin. "Autonomic Profile, Cerbal Autoregulationand Autonomic Modulation in Neurally-Mediated Syncope." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499337.
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Velayos, Muñoz Héctor Luis. "Autonomic wireless networking." Doctoral thesis, KTH, School of Electrical Engineering (EES), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254.
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Large-scale deployment of IEEE 802.11 wireless LANs (WLANs) remains a significant challenge. Many access points (APs) must be deployed and interconnected without a-priori knowledge of the demand. We consider that the deployment should be iterative, as follows. At first, access points are deployed to achieve partial coverage. Then, usage statistics are collected while the network operates. Overloaded and under-utilized APs would be identified, giving the opportunity to relocate, add or remove APs. In this thesis, we propose extensions to the WLAN architecture that would make our vision of iterative deployment feasible.
One line of work focuses on self-configuration, which deals with building a WLAN from APs deployed without planning, and coping with mismatches between offered load and available capacity. Self-configuration is considered at three levels. At the network level, we propose a new distribution system that forms a WLAN from a set of APs connected to different IP networks and supports AP auto-configuration, link-layer mobility, and sharing infrastructure between operators. At the inter-cell level, we design a load-balancing scheme for overlapping APs that increases the network throughput and reduces the cell delay by evenly distributing the load. We also suggest how to reduce the handoff time by early detection and fast active scanning. At the intra-cell level, we present a distributed admission control that protects cells against congestion by blocking stations whose MAC service time would be above a set threshold.
Another line of work deals with self-deployment and investigates how the network can assist in improving its continuous deployment by identifying the reasons for low cell throughput. One reason may be poor radio conditions. A new performance figure, the Multi-Rate Performance Index, is introduced to measure the efficiency of radio channel usage. Our measurements show that it identifies cells affected by bad radio conditions. An additional reason may be limited performance of some AP models. We present a method to measure the upper bound of an AP’s throughput and its dependence on offered load and orientation. Another reason for low throughput may be excessive distance between users and APs. Accurate positioning of users in a WLAN would permit optimizing the location and number of APs. We analyze the limitations of the two most popular range estimation techniques when used in WLANs: received signal strength and time of arrival. We find that the latter could perform better but the technique is not feasible due to the low resolution of the frame timestamps in the WLAN cards.
The combination of self-configuration and self-deployment enables the autonomic operation of WLANs.
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Velayos, Mu~noz Héctor Luis. "Autonomic wireless networking /." Stockholm : Laboratory for Communication Networks, Department of Signals, Sensors and Systems, Royal Institute of Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254.
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Taylor, Paul. "Autonomic business processes." Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/11712/.
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Business processes in large organisations are typically poorly understood and complex in structure. Adapting such a business process to changing internal and external conditions requires costly and time consuming investigative work and change management. In contrast autonomic systems are able to adapt to changing environments and continue to function without external intervention. Enabling business processes to adapt to changing conditions in the same way would be extremely valuable. This work investigates the potential to self-heal individual business process executions in generic business processes. Classical and Immune-inspired classification algorithms are tested for their predictive utility with Decision Trees augmented with MetaCost and Immunos 99 exhibiting the best performance respectively. An approach to deriving recovery strategies from historical process data in the absence of a process model is presented and tested for suitability. Also presented is an approach to selecting the best of the determined recovery strategies for application to a business process execution, which is then tested to determine the impact of its parameters on the quality of selected recoveries.
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Azzam, Adel R. "Survey of Autonomic Computing and Experiments on JMX-based Autonomic Features." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2123.
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Autonomic Computing (AC) aims at solving the problem of managing the rapidly-growing complexity of Information Technology systems, by creating self-managing systems. In this thesis, we have surveyed the progress of the AC field, and studied the requirements, models and architectures of AC. The commonly recognized AC requirements are four properties - self-configuring, self-healing, self-optimizing, and self-protecting. The recommended software architecture is the MAPE-K model containing four modules, namely - monitor, analyze, plan and execute, as well as the knowledge repository.
In the modern software marketplace, Java Management Extensions (JMX) has facilitated one function of the AC requirements - monitoring. Using JMX, we implemented a package that attempts to assist programming for AC features including socket management, logging, and recovery of distributed computation. In the experiments, we have not only realized the powerful Java capabilities that are unknown to many educators, we also illustrated the feasibility of learning AC in senior computer science courses.
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Kalincik, Tomas Medical Sciences Faculty of Medicine UNSW. "Disturbances of autonomic functions in spinal cord injury: autonomic dysreflexia and thermoregulation." Publisher:University of New South Wales. Medical Sciences, 2009. http://handle.unsw.edu.au/1959.4/43516.
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Disorders of the autonomic nervous system constitute serious complications of spinal cord injury (SCI) and their treatment is usually highly prioritised by spinal patients. Among these, autonomic dysreflexia and impaired thermoregulation are potentially life threatening conditions and require effective management. Olfactory ensheathing cells (OECs), progenitor cells and polymeric scaffolds have been tested in animal models of SCI and some of them have been considered for clinical trials. However, evaluation of the effect of such interventions on autonomic functions has received only rudimentary attention and would require a more thorough experimental assessment before the methods are utilised in human patients. This thesis tested two potential therapeutic strategies for autonomic dysreflexia and examined disorders of thermoregulatory functions in a rat model of spinal cord transection. Magnitude and duration of autonomic dysreflexia were evaluated with radio telemetry in spinalised animals treated with (i) implants of OECs and olfactory neurosphere-derived cells seeded in poly(lactic co glycolic) porous scaffolds or with (ii) transplants of OECs alone. (iii) Effects of SCI and of OECs on the morphology of sympathetic preganglionic neurons (SPNs; which are involved in pathogenesis of autonomic dysreflexia) stained for NADPH diaphorase were examined. (iv) Doppler ultrasonography and infrared thermography were used to assess responses of tail blood flow and surface temperature to cold. Transplants of OECs alone, but not in combination with olfactory neurosphere-derived cells and polymeric scaffolds, resulted in significantly shortened episodes of autonomic dysreflexia. This may be attributed to the alterations to the morphology of SPNs adjacent to the lesion: a transient increase in the morphometric features of the SPNs was evoked by spinal cord transection and this was further altered by transplantation of OECs. The thesis also showed that local responses of tail blood flow and temperature to cold were not abolished by complete SCI suggesting that temperature homeostasis could still be maintained in response to cold. It is hypothesised that OECs facilitate improved recovery from autonomic dysreflexia through alteration of the morphology of SPNs. Furthermore, it is suggested that the role of the tail in heat conservation can be regulated by mechanisms that are independent of the descendent neural control from supraspinal centres.
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Vichayanrat, Ekawat. "Autonomic function and non-motor symptoms in primary chronic autonomic failure disorders." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/32259.
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The autonomic nervous system innervates and influences every organ in the body through two major efferent pathways; the sympathetic and parasympathetic nervous systems. Autonomic dysfunction, especially orthostatic hypotension (OH) and olfactory dysfunction, are commonly present in a variety of neurological disorders, particularly, multiple system atrophy (MSA) and allied disorders, such as Parkinson’s disease (PD) and Pure Autonomic Failure (PAF) and can significantly impact quality of life and cause significant morbidity. Similarly, non-motor symptoms have been increasingly recognized in PD. The overlapping autonomic features of PD, PAF and MSA, e.g., OH, can sometimes make it difficult to differentiate a diagnosis between these conditions. The further evaluation of autonomic function, e.g., cardiovascular, olfactory and gastrointestinal function, in patients with primary chronic autonomic failure disorders could offer better diagnostic accuracy, improve the understanding of disease progression and inform the development of treatments. Cardiovascular autonomic function screening tests are commonly used to confirm a diagnosis of autonomic failure, e.g., orthostatic hypotension, but OH is not often reliable for distinguishing between PD and MSA. Novel indices of cardiovascular autonomic function in patients with chronic autonomic failure have therefore been evaluated as well as the severity of olfactory dysfunction and other non-motor (e.g., daily activities and depression) symptoms in MSA, PD and PAF. Results demonstrated that baroreflex sensitivity and blood pressure recovery time (BRPT) in response to the Valsalva Manoeuvre are useful for differentiating MSA from PD with autonomic failure (PD+AF). BPRT was also significantly prolonged in PD patients compared to healthy controls. In addition, an association of BPRT and disease duration in PD also suggests that this index may be useful for monitoring disease progression in PD. Other findings indicated that assessing olfactory function is also helpful for distinguishing between PD, MSA and PAF. A greater degree of depression and impairment of daily activities in MSA relative to PD and PAF were also evident. In order to further investigate the presenting symptoms and features of PAF, a time when diagnosis is often still unclear, and other disorders, such as MSA, can be suspected, the clinical characteristics and laboratory investigations, in a large cohort of PAF patients were examined. Results indicated that abnormal white matter lesions are prevalent in PAF. Furthermore, gastrointestinal symptoms were also evident in PAF and can also occur in other autonomic disorders, e.g., MSA. Using electrogastrography, impaired indexes of gastric motility were also evident in PAF.
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Giordano, Manfredi. "Autonomic Big Data Processing." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14837/.
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Apache Spark è un framework open source per la computazione distribuita su larga scala, caratterizzato da un engine in-memory che permette prestazioni superiori a soluzioni concorrenti nell’elaborazione di dati a riposo (batch) o in movimento (streaming). In questo lavoro presenteremo alcune
tecniche progettate e implementate per migliorare l’elasticità e l’adattabilità del framework rispetto a modifiche dinamiche nell’ambiente di esecuzione o nel workload. Lo scopo primario di tali tecniche è di permettere ad applicazioni concorrenti di condividere le risorse fisiche disponibili nell’infrastruttura cluster
sottostante in modo efficiente. Il contesto nel quale le applicazioni distribuite vengono eseguite difficilmente può essere considerato statico: le componenti hardware possono fallire, i processi possono interrompersi, gli utenti possono allocare risorse aggiuntive in modo imprevedibile nel tentativo di accelerare
la computazione o di allegerire il carico di lavoro. Infine, non soltanto le risorse fisiche ma anche i dati in input possono variare di dimensione e complessità durante l’esecuzione, così che sia dati sia risorse non possano essere considerati statici.
Una configurazione immutabile del cluster non riuscirà a ottenere la migliore efficienza possibile per tutti i differenti carichi di lavoro. Ne consegue che un framework per il calcolo distribuito che sia "consapevole" delle modifiche ambientali e delle modifiche al workload e che sia in grado di adattarsi a esse puo risultare piu performante di un framework che permetta unicamente
configurazioni statiche. Gli esperimenti da noi compiuti con applicazioni Big Data altamente parallelizzabili mostrano come il costo della soluzione proposta sia minimo e come la nostra version di Spark più dinamica e adattiva possa portare a benefici in termini di flessibilità, scalabilità ed efficienza.
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Querido, Jordan Scott. "Hypoxia and autonomic control." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42530.
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Humans have a remarkable ability to cope with and survive exposure to hypoxia. Some have suggested a benefit in certain physiological systems in response to such exposure. However, the physiological response to hypoxia is multifaceted and includes an orchestrated response from many autonomic mechanisms. Thus, the purpose of this thesis was to more fully understand the human autonomic response to hypoxia as an integrated unit. Furthermore, pathological models of hypoxia provide evidence that suggests hypoxia can result in an autonomic response that outlasts the hypoxic stimulus. However, the persistent effect of hypoxia is only evident in certain reflexes, although comorbidities that accompany a pathological model complicate interpretation. Therefore, employing a healthy human model with continued measurement of physiological measures in the post-hypoxia period provides a more complete understanding of the integrated human physiological response to hypoxia. This Doctoral thesis is comprised of four separate investigations, each focusing on autonomic control both during and following an acute hypoxic exposure. In the first study (Chapter 2), the microneurography technique was used to demonstrate that the chemoreflex plays an important role in persistent sympathoexcitation following acute isocapnic hypoxia. With the use of the spontaneous baroreflex analysis technique, the follow-up study (Chapter 3) implicated a resetting of the arterial baroreflex that works to permit the persistent sympathoexcitation. The focus of the third study (Chapter 4) was on cerebrovascular control during fluctuations in blood pressure via bolus injections of vasoactive drugs. There was an improvement in cerebral autoregulation to increases in blood pressure following acute isocapnic hypoxia. The final study (Chapter 5) considered the role of carbon dioxide on hypoxic cerebral autoregulation, and found an impairment in isocapnic hypoxia but no effect in poikilocapnic hypoxia. The findings from this series of studies demonstrate the acute and persistent effects of short-term hypoxia, and the integrated nature in which autonomic mechanisms orchestrate the human physiological response to hypoxia.
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Mendelson, Anita. "Autonomic dysfunction in fibromyalgia." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101729.
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Autonomic nervous system dysfunction characterized by sympathetic hyperactivity at rest and sympathetic hypo-reactivity to physical stressors has been demonstrated in individuals with fibromyalgia. However, little is known regarding the autonomic responses to mental stressors. This study investigated autonomic and subjective responses in 10 female fibromyalgia subjects and 10 age-matched female controls during a physical (active standing) and mental challenge (Stroop word task).There were no group differences in autonomic measures at baseline. However, fibromyalgia subjects were more anxious, fatigued and in more pain. During the active stand task, fibromyalgia subjects had less increase in sympathetic and less decrease in parasympathetic modulations of heart rate compared to controls. However, during the cognitive challenge group differences were not observed in either autonomic or subjective responses. These results confirm previous findings that individuals with fibromyalgia are less reactive to physical challenges than controls, but also suggest that they do not respond differently during mental challenges.
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Adjei, P. "Autonomic function in epilepsy." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1121227/.
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Autonomic function may help to localize and manage the epilepsies. It is likely that the mechanisms of Sudden Unexpected death in Epilepsy (SUDEP) involve autonomic disturbance and a better understanding of these might lead to measures that would help reduce the mortality in patients afflicted with epilepsy. In this thesis, I first provide a comprehensive literature review of the association between epilepsy and the autonomic nervous system. I then evaluate heart rate variability and other cardiac and endocrine parameters as indices of cardiac autonomic function to test three hypothesis; 1) Changes in heart rate variability (HRV), can occur in the peri-ictal period during both (a) subclinical electrographic seizures and (b) clinically overt partial seizures, and can help to localise and lateralise the ictal discharge. 2) Intractable epilepsy can disrupt the heart rate variability and its circadian rhythm. 3) Epileptic seizures affect the serum concentration of the catecholamines and the electrolytes and that these changes could impact on the corrected QT interval. Subjects (n=207) with intractable epilepsy who were being evaluated with video-EEG telemetry for epilepsy surgery were recruited for this study. I found that subclinical seizures have no effect on the HRV. However, in overt partial seizures, HRV decreases, corrected QT is prolonged and plasma catecholamines increases. The reduction in HRV during seizures is not affected by the hemispheric or lobar location of the epileptic focus. However, in the interictal period, reduced HRV differs in left vs. right hemisphere, and in temporal vs. extratemporal areas. The diurnal pattern of HRV is not altered in epilepsy and the mean day HRV were significantly different from mean night HRV. The reduction in HRV is also associated with the following clinical factors: prolonged medical history of epilepsy, the cortical pathology itself, the nature of the seizures, higher seizure frequency and the antiepileptic drug treatment. The plasma electrolytes: Na, K+, Ca2+ and cardiac troponin are not affected after a seizure. However, plasma Mg2+ was seen to increase after a seizure. These abnormalities in autonomic control, particularly the reduction in HRV might be one contributory mechanism of Sudden Unexpected Death in Epilepsy (SUDEP).
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Patelli, Alina. "Knowledge-centric autonomic systems." Thesis, Aston University, 2017. http://publications.aston.ac.uk/37574/.
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Autonomic computing revolutionised the commonplace understanding of proactiveness in the digital world by introducing self-managing systems. Built on top of IBM’s structural and functional recommendations for implementing intelligent control, autonomic systems are meant to pursue high level goals, while adequately responding to changes in the environment, with a minimum amount of human intervention. One of the lead challenges related to implementing this type of behaviour in practical situations stems from the way autonomic systems manage their inner representation of the world. Specifically, all the components involved in the control loop have shared access to the system’s knowledge, which, for a seamless cooperation, needs to be kept consistent at all times. A possible solution lies with another popular technology of the 21st century, the Semantic Web,and the knowledge representation media it fosters, ontologies. These formal yet flexible descriptions of the problem domain are equipped with reasoners, inference tools that, among other functions, check knowledge consistency. The immediate application of reasoners in an autonomic context is to ensure that all components share and operate on a logically correct and coherent “view” of the world. At the same time, ontology change management is a difficult task to complete with semantic technologies alone, especially if little to no human supervision is available. This invites the idea of delegating change management to an autonomic manager, as the intelligent control loop it implements is engineered specifically for that purpose. Despite the inherent compatibility between autonomic computing and semantic technologies,their integration is non-trivial and insufficiently investigated in the literature. This gap represents the main motivation for this thesis. Moreover, existing attempts at provisioning autonomic architectures with semantic engines represent bespoke solutions for specific problems (load balancing in autonomic networking, deconflicting high level policies, informing the process of correlating diverse enterprise data are just a few examples). The main drawback of these efforts is that they only provide limited scope for reuse and cross-domain analysis (design guidelines, useful architectural models that would scale well across different applications and modular components that could be integrated in other systems seem to be poorly represented). This work proposes KAS (Knowledge-centric Autonomic System), a hybrid architecture combining semantic tools such as: • an ontology to capture domain knowledge,• a reasoner to maintain domain knowledge consistent as well as infer new knowledge, • a semantic querying engine,• a tool for semantic annotation analysis with a customised autonomic control loop featuring: • a novel algorithm for extracting knowledge authored by the domain expert, • “software sensors” to monitor user requests and environment changes, • a new algorithm for analysing the monitored changes, matching them against known patterns and producing plans for taking the necessary actions, • “software effectors” to implement the planned changes and modify the ontology accordingly. The purpose of KAS is to act as a blueprint for the implementation of autonomic systems harvesting semantic power to improve self-management. To this end, two KAS instances were built and deployed in two different problem domains, namely self-adaptive document rendering and autonomic decision-support for career management. The former case study is intended as a desktop application, whereas the latter is a large scale, web-based system built to capture and manage knowledge sourced by an entire (relevant) community. The two problems are representative for their own application classes –namely desktop tools required to respond in real time and, respectively, online decision support platforms expected to process large volumes of data undergoing continuous transformation – therefore, they were selected to demonstrate the cross-domain applicability (that state of the art approaches tend to lack) of the proposed architecture. Moreover, analysing KAS behaviour in these two applications enabled the distillation of design guidelines and of lessons learnt from practical implementation experience while building on and adapting state of the art tools and methodologies from both fields. KAS is described and analysed from design through to implementation. The design is evaluated using ATAM (Architecture Trade off Analysis Method) whereas the performance of the two practical realisations is measured both globally as well as deconstructed in an attempt to isolate the impact of each autonomic and semantic component. This last type of evaluation employs state of the art metrics for each of the two domains. The experimental findings show that both instances of the proposed hybrid architecture successfully meet the prescribed high-level goals and that the semantic components have a positive influence on the system’s autonomic behaviour.
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Tunc, Cihan. "Autonomic Cloud Resource Management." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/347144.
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The power consumption of data centers and cloud systems has increased almost three times between 2007 and 2012. The traditional resource allocation methods are typically designed for high performance as the primary objective to support peak resource requirements. However, it is shown that server utilization is between 12% and 18%, while the power consumption is close to those at peak loads. Hence, there is a pressing need for devising sophisticated resource management approaches. State of the art dynamic resource management schemes typically rely on only a single resource such as core number, core speed, memory, disk, and network. There is a lack of fundamental research on methods addressing dynamic management of multiple resources and properties with the objective of allocating just enough resources for each workload to meet quality of service requirements while optimizing for power consumption. The main focus of this dissertation is to simultaneously manage power and performance for large cloud systems. The objective of this research is to develop a framework of performance and power management and investigate a general methodology for an integrated autonomic cloud management. In this dissertation, we developed an autonomic management framework based on a novel data structure, AppFlow, used for modeling current and near-term future cloud application behavior. We have developed the following capabilities for the performance and power management of the cloud computing systems: 1) online modeling and characterizing the cloud application behavior and resource requirements; 2) predicting the application behavior to proactively optimize its operations at runtime; 3) a holistic optimization methodology for performance and power using number of cores, CPU frequency, and memory amount; and 4) an autonomic cloud management to support the dynamic change in VM configurations at runtime to simultaneously optimize multiple objectives including performance, power, availability, etc. We validated our approach using RUBiS benchmark (emulating eBay), on an IBM HS22 blade server. Our experimental results showed that our approach can lead to a significant reduction in power consumption upto 87% when compared to the static resource allocation strategy, 72% when compared to adaptive frequency scaling strategy, and 66% when compared to a multi-resource management strategy.
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Young, Tim. "Cardiovascular autonomic responses in pre- and post-ganglionic models of chronic autonomic failure." Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/4718.
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Multiple System Atrophy (MSA) and Pure Autonomic Failure (PAF) are contrasting models of Chronic Autonomic failure. PAF primarily involves the post-ganglionic autonomic nervous system, whilst in MSA the pre-ganglionic structures are impaired. My central hypothesis is that this underlying neuropathological difference between MSA and PAF will lead to differing cardiovascular responses. I will assess the cardiovascular effects of known pressor and vasomotor stimuli (mental arithmetic, cold pressor test, isometric exercise, water ingestion, inhaled CO₂ and inspiratory gasp) in MSA and PAF. Neurohormonal aspects will be explored by comparing the cardiovascular effects of the α2-adrenoceptor agonist clonidine with serum noradrenaline levels in these groups, as well as comparing supine antidiuretic hormone (ADH) levels after head up tilt and correlating these with supine blood pressure (BP). As well as contrasting the cardiovascular responses, I will use the water ingestion studies to examine effects on orthostatic hypotension, a common complication of both MSA and PAF. To measure cardiovascular responses during these studies I have used the Portapres II device to obtain continuous, non-invasive, beat-to-beat measurements of BP and heart rate (HR). Subsequent Model flow analysis using Beatscope software has then been used to calculate further cardiovascular indices, including cardiac output (CO), stroke volume (SV) and total peripheral resistance (TPR). In addition, intermittent BP and HR measurements have been obtained with an automated sphygmomanometer (Dinamap). Finally, peripheral vasomotor responses have been recorded by means of the Laser Doppler perfusion meter.
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Christie, Israel C. "Behavioral Inhibition/Activation and Autonomic Control of the Heart: Extending the Autonomic Flexibility Model." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27676.
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The autonomic flexibility model has proven to be a useful theoretical tool relating reductions in physiological variability found to accompany anxiety and concomitant reductions in behavioral (e.g., cognitive and emotional) flexibility. The present study aimed to extend the autonomic flexibility model through the inclusion of individual differences in the sensitivity of the independent motivational systems presumed to underlie anxiety and impulsivity, namely the behavioral inhibition and activation systems (BIS/BAS; Gray, 1994). Contrary to the predicted inverse relationship between BIS sensitivity and measures of physiological variability, findings suggest BAS sensitivity is associated with increased trait-like vagally mediated heart rate variability across diverse tasks as well as greater flexibility in responding within tasks. Numerous BIS*BAS interactions emerged as significant predictors of trait reactivity. Results are discussed in terms of the interface between (1) mesolimbic dopaminergic projections to the nucleus accumbens and (2) the network of central nervous system structures believed to play a large role in controlling peripheral physiology.Ph. D.
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Zimmerman, Amanda L. "Neuromodulation of spinal autonomic regulation." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42777.
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The central nervous system is largely responsible for receiving sensory information from the environment and determining motor output. Yet, centrally-derived behavior and sensation depends on the optimal maintenance of the cells, tissues, and organs that feed and support these functions. Most of visceral regulation occurs without conscious oversight, making the spinal cord a key site for integration and control. How the spinal cord modulates output to our organs, or sensory information from them, is poorly understood.
The overall aim of this dissertation was to better understand spinal processing of both visceral sensory information to and sympathetic output from the spinal cord. I first established and validated a HB9-GFP transgenic mouse model that unambiguously identified sympathetic preganglionic neurons (SPNs), the spinal output neurons for the sympathetic nervous system. Using this model, I investigated the electrophysiological similarities and diversity of SPNs, and compared their active and passive membrane properties to those in other animal models. My results indicate that while many of the same characteristics are shared, SPNs are a heterogeneous group that can be differentiated based on their electrophysiological properties.
Since descending monoaminergic pathways have particularly dense projections to sympathetic regions of the spinal cord, I next examined the modulatory role that the monoamines have on spinal sympathetic output. While each neuromodulator tested had a unique signature of action, serotonin and norepinephrine appeared to increase the excitability of individual SPNs, while dopamine had more mixed actions. Since many autonomic reflexes are integrated by the spinal cord, I also questioned whether these reflexes would be similarly modulated. I therefore developed a novel in vitro spinal cord and sympathetic chain preparation, which allowed for the investigation of visceral afferent-mediated reflexes and their neuromodulation by monoamines. This preparation exposed a dichotomy of action, where sympathetic and somatic motor output is generally enhanced by the monoamines, but reflexes mediated by visceral input are depressed.
Utilizing the spinal cord and sympathetic chain preparation, I also investigated how the spinal cord modulates visceral sensory information. One of the most powerful means of selectively inhibiting afferent information from reaching the spinal cord is presynaptic inhibition. I hypothesized that both spinal visceral afferents and descending monoaminergic systems would depress transmission of visceral afferents to the spinal cord. My results demonstrated that activity in spinal visceral afferents can lead to spinally generated presynaptic inhibition, and that in addition to depressing synaptic transmission to the spinal cord, the monoamines also depress the intrinsic circuitry that generates this activity-dependent presynaptic inhibition.
Taken together, my results indicate that descending monoaminergic pathways act to limit the amount of visceral sensory information reaching the central nervous system and increase sympathetic output, resulting in an uncoupling of output from visceral sensory input and transitioning to a feed-forward, sympathetically dominant control strategy. This combination offers complex modulatory strategies for descending systems.
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Steele, Shelby L. "Autonomic Control of Cardiac Function." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19763.
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Cardiac parasympathetic tone mediates hypoxic bradycardia in fish, however the specific cholinergic mechanisms underlying this response have not been established. In Chapter 2, bradycardia in zebrafish (Danio rerio) larvae experiencing translational knockdown of the M2 muscarinic receptor was either prevented or limited at two different levels of hypoxia (PO2 = 30 or 40 Torr). Also, M2 receptor deficient fish exposed to exogenous procaterol (a presumed β2-adrenergic receptor agonist) had lower heart rates than similarly treated control fish, implying that the β2-adrenergic receptor may have a cardioinhibitory role in this species.
Zebrafish have a single β1-adrenergic receptor (β1AR), but express two distinct β2-adrenergic receptor genes (β2aAR and β2bAR). Zebrafish β1AR deficient larvae described in Chapter 3 had lower resting heart rates than control larvae, which conforms to the stereotypical stimulatory nature of this receptor in the vertebrate heart. However, in larvae where loss of β2a/β2bAR and β1/β2bAR function was combined, heart rate was significantly increased. This confirmed my previous observation that the β2-adrenergic receptor has an inhibitory effect on heart rate in vivo.
Fish release the catecholamines epinephrine and norepinephrine (the endogenous ligands of adrenergic receptors) into the circulation when exposed to hypoxia, if sufficiently severe. Zebrafish have two genes for tyrosine hydroxylase (TH1 and TH2), the rate limiting enzyme for catecholamine synthesis, which requires molecular oxygen as a cofactor. In Chapter 4, zebrafish larvae exposed to hypoxia for 4 days exhibited increased whole body epinephrine and norepinephrine content. TH2, but not TH1, mRNA expression decreased after 2 days of hypoxic exposure.
The results of this thesis provide some of the first data on receptor-specific control of heart rate in fish under normal and hypoxic conditions. It also provides the first observations that catecholamine turnover and the mRNA expression of enzymes required for catecholamine synthesis in larvae are sensitive to hypoxia. Taken together, these data provide an interesting perspective on the balance of adrenergic and cholinergic control of heart rate in zebrafish larvae.
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SALLES, MARCOS ANTONIO VAZ. "AUTONOMIC INDEX CREATION IN DATABASES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=5790@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORA escolha e materialização de índices são atividades comumente realizadas por administradores de bancos de dados (DBAs) para acelerar o processamento de aplicações de bancos de dados. Devido à complexidade da tarefa de seleção de índices e à pressão por maior produtividade sobre os profissionais que realizam sintonia, diversos trabalhos na literatura e em sistemas comerciais procuram obter ferramentas que possam apoiar o DBA na escolha dos melhores índices para uma dada carga de trabalho. Classificamos estes trabalhos como sendo de auto-sintonia local, uma vez que se focam em um problema de sintonia específico, em oposição a trabalhos de auto-sintonia global, que almejam obter um desempenho aceitável para o sistema como um todo. Esta dissertação propõe duas arquiteturas que permitem automatizar completamente a sintonia de índices. A indepedência de intervenção humana é obtida através do uso de agentes de software. A combinação de agentes com SGBDs torna os sistemas mais autônomos e capazes de auto-sintonia. Implementamos uma das arquiteturas propostas no SGBD de código fonte aberto PostgreSQL e obtivemos resultados experimentais com uma carga transacional que mostram a viabilidade de nossa abordagem.
The choice and materialization of indexes are activities commonly done by database administrators to speed up database application processing. Due to the complexity of the index selection task and to the pressure for productivity increase put on tuning professionals, many works on the literature and on commercial systems seek for tools that can help the DBA choose the best indexes for a given workload. We classify these works as local self- tuning, once they are interested in a specific tuning problem, in opposition to global self-tuning work, which is targeted at obtaining acceptable performance for the system as a whole. This dissertation proposes two architectures that allow the complete automation of the index tuning task. Human intervention independence is achieved through the use of software agents. The combination of agents and DBMS makes systems more autonomous and self-tuning. We have implemented one of the proposed architectures in the open source DBMS PostgreSQL and obtained experimental results with a transactional workload that show the feasibility of our approach.
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Whittle, J. "Autonomic dysfunction and perioperative outcome." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1557406/.
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OBJECTIVE: To examine the relationship between established autonomic dysfunction, measures of cardiopulmonary physiology and perioperative outcome in high-risk patients presenting for major surgery. SUMMARY BACKGROUND DATA: Experimental data demonstrate that autonomic activity is a key modulator of both cardiovascular and immune function following tissue injury and inflammation. Autonomic dysfunction is associated with adverse outcomes across several medical populations. Whether pre-existing autonomic dysfunction is detrimental following controlled tissue injury (surgery) in humans is unknown. SUMMARY OF STUDIES: Parasympathetic autonomic dysfunction (PAD), defined by impaired heart rate recovery after exercise, was associated with a distinct physiological profile in patients presenting for preoperative Cardiopulmonary Exercise Testing (CPET). This comprised impaired cardiac performance at peak exercise, reduced peak oxygen uptake and anaerobic threshold as well as chronotropic incompetence. Levels of GRK2, a regulator of beta adrenoreceptor and immune/inflammatory activity, in circulating lymphocytes were raised in cells derived from individuals with PAD. Retrospective analysis of outcomes from two prospectively collected colorectal surgical cohorts (n=1047) revealed PAD to be common (>30%) and associated with an increased length of hospital stay (12 days (95% CI: 9-16) vs. 8 days (95% CI: 6-8.5), p=0.01), as well as increased risk of significant Clavien-Dindo defined morbidity, postoperative gastrointestinal function, sepsis and increased 90-day mortality (RR 1.1 (1.007-1.41), p=0.008). Intraoperative haemodynamic data indicated impaired cardiac contractility and increased risk of intraoperative hypotension, possibly contributing to detriments in postoperative outcome. Sympathetic autonomic hyperactivity, defined by excessive anticipatory heart rate rise prior to starting loaded exercise was associated with a different CPET profile to that seen in PAD, defined by evidence of cardiac ischaemia during exercise, resulting in impaired cardiac contractile function at peak effort, but also associated with increased hospital length of stay. Patients with PAD did not necessarily demonstrate sympathetic hyperactivity, but when both were present, physiological performance and postoperative outcomes were further impaired. Conclusions: Both preoperative parasympathetic and sympathetic autonomic dysfunction are associated with impaired perioperative outcomes. These data demonstrate in high risk surgical patients that established autonomic dysregulation is associated with the development of sepsis, myocardial ischaemia, critical illness and mortality following major elective surgery. The autonomic nervous system represents an underexplored target for therapies aimed at reducing the morbidity burden of major surgery.
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Adlan, Ahmed. "Autonomic function in rheumatoid arthritis." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6705/.
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Rheumatoid arthritis (RA) is a chronic inflammatory condition with poorly understood pathophysiology and increased cardiovascular risk. The mechanisms for increased cardiovascular risk are not fully known, however one novel mechanism explored in this thesis is autonomic nervous system (ANS) dysfunction. The thesis comprises of: a systematic literature review; two case-control studies (n=30 RA patients, n=34 controls; a longitudinal case-study (n=1 RA patient)); a cohort study (n=112 RA patients); and a randomised placebo controlled crossover study (n=10 healthy controls). The work presented in this thesis demonstrates that ANS dysfunction is prevalent in ~60 % of RA patients and characterised by heightened sympathetic outflow to the peripheral vasculature (determined by muscle sympathetic nerve activity using microneurography), depressed baroreflex control of heart rate (determined using the modified Oxford technique), depressed heart rate variability and heightened vascular responses to stressors (cold pressor test and mental stress). Inflammation was associated with ANS dysfunction, and may well contribute to the increased cardiovascular risk seen in RA. Further studies are required to: confirm these findings; determine whether therapeutic strategies to restore ANS function improve prognosis in RA; and further explore the precise mechanisms by which inflammatory cytokines may influence ANS function in health and disease.
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Daley, John. "Autonomic product development process automation /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1958.pdf.
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Daley, John E. "Autonomic Product Development Process Automation." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/965.
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Market globalization and mass customization requirements are forcing companies towards automation of their product development processes. Many task-specific software solutions provide localized automation. Coordinating these local solutions to automate higher-level processes requires significant software maintenance costs due to the incompatibility of the software tools and the dynamic nature of the product development environment. Current automation methods do not provide the required level of flexibility to operate in this dynamic environment. An autonomic product development process automation strategy is proposed in order to provide a flexible, standardized approach to product development process automation and to significantly reduce the software maintenance costs associated with traditional automation methods. Key elements of the strategy include a formal approach to decompose product development processes into services, a method to describe functional and quality attributes of services, a process modeling algorithm to configure processes composed of services, a method to evaluate process utility based on quality metrics and user preferences, and an implementation that allows a user to instantiate the optimal process. Because the framework allows a user to rapidly reconfigure and select optimal processes as new services are introduced or as requirements change, the framework should reduce burdensome software maintenance costs associated with traditional automation methods and provide a more flexible approach.
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Kallio, M. (Mika). "Cardiovascular autonomic dysfunction in Parkinsonian syndromes." Doctoral thesis, University of Oulu, 2001. http://urn.fi/urn:isbn:9514264487.
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Abstract
Autonomic nervous system (ANS) disturbances are common in Parkinson's
disease (PD), but also in other Parkinsonian syndromes, especially in multiple
system atrophy (MSA). The differentiation between various Parkinsonian syndromes
may be difficult, but it is important for prognostic and therapeutic purposes.
The aim of this study was to determine the ability of different analysis methods
to reveal cardiovascular regulation disturbances in PD and to evaluate the
diagnostic capacity of autonomic tests to differentiate between various
Parkinsonian syndromes. Furthermore, this study aimed to evaluate the
relationships between ANS disturbances and the clinical characteristics of PD. In
addition, the cardiac autonomic function was evaluated during various sleep
stages for the first time in untreated PD patients by using spectral heart rate
variability (HRV) measures to determine possible sleep stage specific
cardiovascular regulation disturbances.
Cardiovascular autonomic reflexes were evaluated in 62 untreated and newly
diagnosed PD patients, 34 PD patients under antiparkinsonian medication, 47 MSA
patients and 15 patients with progressive supranuclear palsy (PSP). The
usefulness of different analysis methods was evaluated in a subgroup of 32
untreated PD patients. A further 21 untreated PD patients underwent one-night
polysomnography for nocturnal heart rate variability analysis.
PD patients with hypokinesia/rigidity as their initial onset sign had a
significantly lower max-min ratio in the deep breathing test than those patients
with tremor as the initial sign. MSA patients showed significant reductions in
both HRV and blood pressure responses during orthostatic provocation, whereas PSP
patients had normal results. Absolute spectral measures yielded the clearest
indicators separating the PD patients from the controls, while the cardiovascular
reflexes proved more useful than the normalised spectral HRV measures in
revealing the differences between the two groups. HRV was abnormally decreased
during non-REM sleep in PD patients but not during REM sleep or the S1 sleep
stage. The normalized high frequency power was significantly decreased in PD
patients during sleep stages S2-4, while the standard deviation of the R-R
intervals was increased during the same sleep stages, possibly corresponding to
the increased motility of PD patients during these sleep stages.
The clinical characteristics of PD deserve particular attention in
connection with ANS disturbances, since autonomic failure seems to be more
pronounced in PD patients with hypokinesia/rigidity as their initial sign. The
evaluation of the autonomic function may also be helpful in the differential
diagnosis of Parkinsonian syndromes. Spectral analysis methods should be
implemented in the evaluation of ANS dysfunction to achieve the best possible
efficacy in the differentiation of pathological responses from normal ones.
Nocturnal analysis of cardiovascular regulation revealed new and interesting
features of pathologic HRV in PD patients, thus when HRV is evaluated, the
different sleep stages should be analysed separately.
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Ylitalo, A. (Antti). "Cardiovascular autonomic regulation in systemic hypertension." Doctoral thesis, Oulun yliopisto, 1999. http://urn.fi/urn:isbn:9514252128.
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Abstract
Neurogenic factors are known to be important in the development of hypertension. Our current knowledge of the role of autonomic nervous system in chronic hypertension is, however, limited. The purpose of the present study was to evaluate the possible abnormalities in heart rate variability (HRV) and baroreflex sensitivity (BRS) in patients with long standing systemic hypertension compared to subjects without evidence of cardiovascular disease. A particular aim was also to examine whether genetic variation in the renin-angiotensin-aldosterone system (RAS) genes have an influence on cardiovascular autonomic regulation.
Case-control studies were carried out on a total of 280 normotensive and 214 hypertensive subjects drawn from a random middle-aged population originally recruited for an epidemiologic study of cardiovascular risk factors. The possible association of BRS with the genetic polymorphisms of renin-angiotensin-aldosterone system genes was studied in a cross-sectional study of 315 healthy controls. Genetic associations were also tested in a younger, independent population sample of 66 subjects. The effects of intensified antihypertensive treatment on autonomic cardiovascular control were evaluated in 33 hypertensive patients with poor blood pressure control.
Wide interindividual variation in both HRV and BRS was observed in normotensive as well as hypertensive subjects. Overall HRV and autonomic responses to a change in body posture were blunted in long-standing hypertension. Decreased HRV was mainly related to elevated blood pressure and obesity.
For the first time in a population-based study, it was confirmed that BRS is impaired in patients with long-standing hypertension despite adequate antihypertensive treatment. In contrast to HRV, BRS was reduced in hypertensive subjects also after adjustment for blood pressure and obesity. BRS also varied widely both between healthy and hypertensive individuals. The wide interindividual variation in the markers of autonomic cardiovascular regulation was not, however, completely explained by demographic variables, cardiovascular risk factors or lifestyle, suggesting a genetic component contributing to HRV and BRS.
The polymorphism in the aldosterone synthase (CYP11B2) gene was found to strongly associate with BRS in two independent random populations of apparently healthy subjects. The association was even stronger in the younger population. On the basis of the observations made in the older population, it seems possible that women are protected against the effect of age and blood pressure on BRS and tend to maintain the genomic influence longer.
Intensified antihypertensive combination therapy improved blood pressure control and caused regression of left ventricular hypertrophy, and resulted in significant improvements of HRV and BRS.
The present study shows that HRV and BRS are altered in long-standing systemic hypertension. Together with age, blood pressure and obesity, genetic factors seem to be important determinants of BRS. However, abnormal autonomic cardiovascular regulation does not seem to be an irreversible phenomenon, but can be partly restored by modern combination antihypertensive therapy.
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King, Andrew B. "Human forebrain control of autonomic function." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ30802.pdf.
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Nakrani, Sunil. "Biomimetic and autonomic server ensemble orchestration." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534214.
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This thesis addresses orchestration of servers amongst multiple co-hosted internet services such as e-Banking, e-Auction and e-Retail in hosting centres. The hosting paradigm entails levying fees for hosting third party internet services on servers at guaranteed levels of service performance. The orchestration of server ensemble in hosting centres is considered in the context of maximising the hosting centre's revenue over a lengthy time horizon. The inspiration for the server orchestration approach proposed in this thesis is drawn from nature and generally classed as swarm intelligence, specifically, sophisticated collective behaviour of social insects borne out of primitive interactions amongst members of the group to solve problems beyond the capability of individual members. Consequently, the approach is self-organising, adaptive and robust. A new scheme for server ensemble orchestration is introduced in this thesis. This scheme exploits the many similarities between server orchestration in an internet hosting centre and forager allocation in a honeybee (Apis mellifera) colony. The scheme mimics the way a honeybee colony distributes foragers amongst flower patches to maximise nectar influx, to orchestrate servers amongst hosted internet services to maximise revenue. The scheme is extended by further exploiting inherent feedback loops within the colony to introduce self-tuning and energy-aware server ensemble orchestration. In order to evaluate the new server ensemble orchestration scheme, a collection of server ensemble orchestration methods is developed, including a classical technique that relies on past history to make time varying orchestration decisions and two theoretical techniques that omnisciently make optimal time varying orchestration decisions or an optimal static orchestration decision based on complete knowledge of the future. The efficacy of the new biomimetic scheme is assessed in terms of adaptiveness and versatility. The performance study uses representative classes of internet traffic stream behaviour, service user's behaviour, demand intensity, multiple services co-hosting as well as differentiated hosting fee schedule. The biomimetic orchestration scheme is compared with the classical and the theoretical optimal orchestration techniques in terms of revenue stream. This study reveals that the new server ensemble orchestration approach is adaptive in a widely varying external internet environments. The study also highlights the versatility of the biomimetic approach over the classical technique. The self-tuning scheme improves on the original performance. The energy-aware scheme is able to conserve significant energy with minimal revenue performance degradation. The simulation results also indicate that the new scheme is competitive or better than classical and static methods.
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Sifalakis, Manolis. "Adaptation and awareness for autonomic systems." Thesis, Lancaster University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531729.
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Poole, Sarah Louise. "Neuropeptide modulation of medullary autonomic circuits." Thesis, University of Leeds, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434147.
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Ramaswamy, Priya M. Eng Massachusetts Institute of Technology. "Analyzing autonomic activity in neonatal seizures." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66805.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 54-55).
Recent studies suggest that seizures in the newborn occur more often than previously appreciated. The effect of neonatal seizures remain unclear, however. Do seizures in the newborn cause brain injury, are they a consequence of brain injury, or are they benign? Seizures in the newborn tend to occur without overt clinical correlates, such as convulsions, so their diagnosis requires electroencephalography (EEG). In this thesis, we investigate whether seizure activity is associated with changes in the discharge pattern of the autonomic nervous system, which could be picked up in heart rate (HR) or heart-rate variability (HRV) analysis. More fundamentally, we seek to investigate whether seizures in the neonate are confined to the cerebral cortex or whether they might originate from or propagate to deeper brain structures. Prior studies have provided some evidence that neonatal seizures can result in HR and HRV changes. From these past studies, there seems to be a heart-brain connection, however, this connection is currently poorly understood. Our long term goal is to understand the connection between electro-cortical activity, electro-cardiac activity, and brain injury in newborns with seizures. In this study, we analyzed the EEG and the electrocardiogram (ECG) signals in fourteen newborns with neonatal stroke and three newborns with hypoxemic-ischemic encephalopathy. Furthermore, we used information from magnetic resonance imaging and magnetic resonance spectroscopy reports to identify injury location in these full-term newborns. Our results indicate that some babies show strong changes in HR and HRV during seizure episodes while others tend to respond very weakly. Due to the small sample size of our patient population, no consistent picture emerged whether the location of injury might be responsible for this response pattern. We also explored a spectrogram-based method to determine the occurrence of seizure (on a lead-by-lead basis) and to determine seizure propagation from one region of the cortex to another.
by Priya Ramaswamy.
M.Eng.
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Scogland, Thomas R. "Runtime Adaptation for Autonomic Heterogeneous Computing." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/71315.
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Heterogeneity is increasing across all levels of computing, with the rise of accelerators such as GPUs, FPGAs, and other coprocessors into everything from cell phones to supercomputers. More quietly it is increasing with the rise of NUMA systems, hierarchical caching, OS noise, and a myriad of other factors. As heterogeneity becomes a fact of life, efficiently managing heterogeneous compute resources is becoming a critical, and ever more complex, task. The focus of this dissertation is to lay the foundation for an autonomic system for heterogeneous computing, employing runtime adaptation to improve performance portability and performance consistency while maintaining or increasing programmability. We investigate heterogeneity arising from a myriad of factors, grouped into the dimensions of locality and capability. This work has resulted in runtime schedulers capable of automatically detecting and mitigating heterogeneity in physically homogeneous systems through MPI and adaptive coscheduling for physically heterogeneous accelerator based systems as well as a synthesis of the two to address multiple levels of heterogeneity as a coherent whole. We also discuss our current work towards the next generation of fine-grained scheduling and synchronization across heterogeneous platforms in the design of a highly-scalable and portable concurrent queue for many-core systems. Each component addresses aspects of the urgent need for automated management of the extreme and ever expanding complexity introduced by heterogeneity.Ph. D.
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Furrer, Frank J., and Georg Püschel. "From Algorithmic Computing to Autonomic Computing." Technische Universität Dresden, 2018. https://tud.qucosa.de/id/qucosa%3A30773.
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In algorithmic computing, the program follows a predefined set of rules – the algorithm. The analyst/designer of the program analyzes the intended tasks of the program, defines the rules for its expected behaviour and programs the implementation. The creators of algorithmic software must therefore foresee, identify and implement all possible cases for its behaviour in the future application!
However, what if the problem is not fully defined? Or the environment is uncertain? What if situations are too complex to be predicted? Or the environment is changing dynamically? In many such cases algorithmic computing fails.
In such situations, the software needs an additional degree of freedom: Autonomy! Autonomy allows software to adapt to partially defined problems, to uncertain or dynamically changing environments and to situations that are too complex to be predicted. As more and more applications – such as autonomous cars and planes, adaptive power grid management, survivable networks, and many more – fall into this category, a gradual switch from algorithmic computing to autonomic computing takes place.
Autonomic computing has become an important software engineering discipline with a rich literature, an active research community, and a growing number of applications.:Introduction 5
1 A Process Data Based Autonomic Optimization of Energy Efficiency in Manufacturing Processes, Daniel Höschele 9
2 Eine autonome Optimierung der Stabilität von Produktionsprozessen auf Basis von Prozessdaten, Richard Horn 25
3 Assuring Safety in Autonomous Systems, Christian Rose 41
4 MAPE-K in der Praxis - Grundlage für eine mögliche automatische Ressourcenzuweisung, in der Cloud Michael Schneider 59
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Dudzik, Stefan Einhorn Jochen Schönleber Tim. "Untersuchung des IBM Autonomic Computing Toolkits." [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11730082.
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Jiang, Tao. "Distributed trust management in autonomic networks." College Park, Md.: University of Maryland, 2007. http://hdl.handle.net/1903/7769.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.Thesis research directed by: Dept. of Electrical and Computer Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Van, Male Lynn M. "Autonomic characteristics of sexual trauma survivors /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9988705.
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Loreti, Daniela <1984>. "Autonomic Management of Cloud Virtual Infrastructures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7424/1/loreti_daniela_tesi.pdf.
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The new model of interaction suggested by Cloud Computing has experienced a significant diffusion over the last years thanks to its capability of providing customers with the illusion of an infinite amount of reliable resources. Nevertheless, the challenge of efficiently manage a large collection of virtual computing nodes has just been partially moved from the customer's private datacenter to the larger provider's infrastructure that we generally address as “the cloud”. A lot of effort - in both academic and industrial field - is therefore concentrated on policies for the efficient and autonomous management of virtual infrastructures.
The research on this topic is further encouraged by the diffusion of cheap and portable sensors and the availability of almost ubiquitous Internet connectivity that are constantly creating large flows of information about the environment we live in. The need for fast and reliable mechanisms to process these considerable volumes of data has inevitably pushed the evolution from the initial scenario of a single (private or public) cloud towards cloud interoperability, giving birth to several forms of collaboration between clouds. The efficient resource management is further complicated in these heterogeneous environments, making autonomous administration more and more desirable.
In this thesis, we initially focus on the challenges of autonomic management in a single-cloud scenario, considering the benefits and shortcomings of centralized and distributed solutions and proposing an original decentralized model.
Later in this dissertation, we face the challenge of autonomic management in large interconnected cloud environments, where the movement of virtual resources across the infrastructure nodes is further complicated by the intrinsic heterogeneity of the scenario and difficulties introduced by the higher latency medium between datacenters. According to that, we focus on the cost model for the execution of distributed data-intensive application on multiple clouds and we propose different management policies leveraging cloud interoperability.
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Loreti, Daniela <1984>. "Autonomic Management of Cloud Virtual Infrastructures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7424/.
Full textAbstract:
The new model of interaction suggested by Cloud Computing has experienced a significant diffusion over the last years thanks to its capability of providing customers with the illusion of an infinite amount of reliable resources. Nevertheless, the challenge of efficiently manage a large collection of virtual computing nodes has just been partially moved from the customer's private datacenter to the larger provider's infrastructure that we generally address as “the cloud”. A lot of effort - in both academic and industrial field - is therefore concentrated on policies for the efficient and autonomous management of virtual infrastructures.
The research on this topic is further encouraged by the diffusion of cheap and portable sensors and the availability of almost ubiquitous Internet connectivity that are constantly creating large flows of information about the environment we live in. The need for fast and reliable mechanisms to process these considerable volumes of data has inevitably pushed the evolution from the initial scenario of a single (private or public) cloud towards cloud interoperability, giving birth to several forms of collaboration between clouds. The efficient resource management is further complicated in these heterogeneous environments, making autonomous administration more and more desirable.
In this thesis, we initially focus on the challenges of autonomic management in a single-cloud scenario, considering the benefits and shortcomings of centralized and distributed solutions and proposing an original decentralized model.
Later in this dissertation, we face the challenge of autonomic management in large interconnected cloud environments, where the movement of virtual resources across the infrastructure nodes is further complicated by the intrinsic heterogeneity of the scenario and difficulties introduced by the higher latency medium between datacenters. According to that, we focus on the cost model for the execution of distributed data-intensive application on multiple clouds and we propose different management policies leveraging cloud interoperability.
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Kazadi, Lubobo-Claude. "The effects of gastric and homeostatic autonomic afferent reflexes on cardiac autonomic efferent activity in healthy human volunteers." Thesis, University of Wolverhampton, 2015. http://hdl.handle.net/2436/600498.
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The effects of gastric autonomic afferent reflexes on cardiovascular autonomic efferent activity are regarded as a direct neural effect of the activation of gastric receptors which send afferent inputs to the central nervous system (CNS) to cause various cardiovascular changes (Van Orshoven et al., 2004; McHugh et al., 2010; Girona et al., 2014). However, the cardiovascular responses to liquid ingestion in humans may be related to gastric distension, volume loading effects, or to its osmotic proprieties. The purpose of this study was to investigate cross autonomic reflex function and to elucidate the effects of the resulting cardiac efferent autonomic activity in resting young healthy subjects. The ingestion of 300 mL of isothermic water increased both the cardiac vagal tone as indicated by increased RMSSD (mean 23.95 ± 20.50 msec increase, p<0.05) and sympathetic activity shown by increased QTc interval (mean 9.86 ± 8.59 msec increase, p< 0.05) during the first 40 minutes post-ingestion. These effects were absent with an identical volume of a physiological (0.9% w/v) saline solution which would increase plasma volume more, indicating that the cardiovascular responses to water drinking are influenced by its hypo-osmotic properties, rather than being related to the volume loading effects. Nevertheless, subjects responded to gastric distension with an ingestion of 300 mL of Fybogel solution with an increase in sympathetic activity during the first 20 minutes post-ingestion, but not in cardiac vagal tone. These results indicate that the mechanisms underlying the cardiovascular responses to water ingestion have additional components to the gastric stretch effect. Contrarily, the cold mediated sympathetic inhibition after drinking the same volume of either cold water or cold Fybogel solution probably happened in the NTS where the two branches of the ANS meet for the first time during their central pathway (Kubin et al., 2006; Thayer and Lane, 2009). In conclusion, the cardiovascular responses to water drinking are influenced by its hypo-osmolality properties and temperature, not by the volume loading effects.
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Belhaj, Nabila. "Generic autonomic service management for component-based applications." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLL004/document.
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Au cours de la dernière décennie, la complexité des applications a considérablement évolué afin de répondre aux besoins métiers émergeants. Leur conception implique une composition distribuée de composants logiciels. Ces applications fournissent des services à travers les interactions métiers maintenues par leurs composants. De telles applications sont intrinsèquement en évolution dynamique en raison de la dynamicité de leurs contextes. En effet, elles évoluent dans des environnements qui changent tout en présentant des conditions très dynamiques durant leur cycle de vie d’exécution. De tels contextes représentent une lourde charge pour les développeurs aussi bien pour leurs tâches de conception que de gestion. Cela a motivé́ le besoin de renforcer l’autonomie de gestion des applications pour les rendre moins dépendantes de l’intervention humaine en utilisant les principes de l’Informatique Autonomique. Les Systèmes Informatiques Autonomes (SIA) impliquent l’utilisation des boucles autonomiques, dédiées aux systèmes afin de les aider à accomplir leurs tâches de gestion. Ces boucles ont pour objectif d’adapter leurs systèmes à la dynamicité de leurs contextes, en se basant sur une logique d’adaptation intégrée. Cette logique est souvent donnée par des règles statiques codées manuellement. La construction de ces règles demande beaucoup de temps tout en exigeant une bonne expertise. En fait, elles nécessitent une compréhension approfondie de la dynamicité du système afin de prédire les adaptations précises à apporter à celui-ci. Par ailleurs, une telle logique ne peut envisager tous les scénarios d’adaptation possibles, donc, ne sera pas en mesure de prendre en compte des adaptations pour des situations précédemment inconnues. Les SIA devraient donc être assez sophistiqués afin de pouvoir faire face à la nature dynamique de leurs contextes et de pouvoir apprendre par eux-mêmes afin d’agir correctement dans des situations inconnues. Les SIA devraient également être capables d’apprendre de leur propre expérience passée afin de modifier leur logique d’adaptation en fonction de la dynamicité de leurs contextes. Dans ce manuscrit, nous abordons les lacunes décrites en utilisant les techniques d’Apprentissage par Renforcement (AR) afin de construire notre logique d’adaptation. Cependant, les approches fondées sur l’AR sont connues pour leur mauvaise performance lors des premières phases d’apprentissage. Cette mauvaise performance entrave leur utilisation dans le monde réel des systèmes déployés. Par conséquent, nous avons amélioré cette logique d’adaptation avec des capacités d’apprentissage plus performantes avec une approche AR en multi-pas. Notre objectif est d’optimiser la performance de l’apprentissage et de le rendre plus efficace et plus rapide, en particulier durant les premières phases d’apprentissage. Nous avons aussi proposé́ un cadriciel générique visant à aider les développeurs dans la construction d’applications auto-adaptatives. Nous avons donc proposé de transformer des applications existantes en ajoutant des capacités d’autonomie et d’apprentissage à leurs composants. La transformation consiste en l’encapsulation des composants dans des conteneurs autonomiques pour les doter du comportement auto-adaptatif nécessaire. Notre objectif est d’alléger la charge des tâches de gestion des développeurs et de leur permettre de se concentrer plus sur la logique métier de leurs applications. Les solutions proposées sont destinées à être génériques, granulaires et basées sur un standard connu, à savoir l’Architecture de Composant de Service. Enfin, nos propositions ont été évaluées et validées avec des résultats expérimentaux. Ils ont démontré leur efficacité en montrant un ajustement dynamique des applications transformées face aux dynamicités de leurs contextes en un temps beaucoup plus court comparé aux approches existantesDuring the past decade, the complexity of applications has significantly scaled to satisfy the emerging business needs. Their design entails a composition of distributed and interacting software components. They provide services by means of the business interactions maintained by their components. Such applications are inherently in a dynamic evolution due to their context dynamics. Indeed, they evolve in changing environments while exhibiting highly dynamic conditions during their execution life-cycle (e.g., their load, availability, performance, etc.). Such contexts have burdened the applications developers with their design and management tasks. Subsequently, motivated the need to enforce the autonomy of their management to be less dependent on human interventions with the Autonomic Computing principles. Autonomic Computing Systems (ACS) implies the usage of autonomic loops, dedicated to help the system to achieve its management tasks. These loops main role is to adapt their associated systems to the dynamic of their contexts by acting upon an embedded adaptation logic. Most of time, this logic is given by static hand-coded rules, often concern-specific and potentially error-prone. It is undoubtedly time and effort-consuming while demanding a costly expertise. Actually, it requires a thorough understanding of the system design and dynamics to predict the accurate adaptations to bring to the system. Furthermore, such logic cannot envisage all the possible adaptation scenarios, hence, not able to take appropriate adaptations for previously unknown situations. ACS should be sophisticated enough to cope with the dynamic nature of their contexts and be able to learn on their own to properly act in unknown situations. They should also be able to learn from their past experiences and modify their adaptation logic according to their context dynamics. In this thesis manuscript, we address the described shortcomings by using Reinforcement Learning (RL) techniques to build our adaptation logic. Nevertheless, RL-based approaches are known for their poor performance during the early stages of learning. This poor performance hinders their usage in real-world deployed systems. Accordingly, we enhanced the adaptation logic with sophisticated and better-performing learning abilities with a multi-step RL approach. Our main objective is to optimize the learning performance and render it timely-efficient which considerably improves the ACS performance even during the beginning of learning phase. Thereafter, we pushed further our work by proposing a generic framework aimed to support the application developers in building self-adaptive applications. We proposed to transform existing applications by dynamically adding autonomic and learning abilities to their components. The transformation entails the encapsulation of components into autonomic containers to provide them with the needed self-adaptive behavior. The objective is to alleviate the burden of management tasks on the developers and let them focus on the business logic of their applications. The proposed solutions are intended to be generic, granular and based on a well known standard (i.e., Service Component Architecture). Finally, our proposals were evaluated and validated with experimental results. They demonstrated their effectiveness by showing a dynamic adjustment to the transformed application to its context changes in a shorter time as compared to existing approaches
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Tauber, Markus. "Autonomic management in a distributed storage system." Thesis, St Andrews, 2010. http://hdl.handle.net/10023/926.
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Hilding, Emma. "Autonomic responses to subliminally processed positive stimuli." Thesis, Stockholm University, Department of Psychology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7338.
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Subconsciously processed fearful stimuli are routed via the limbic system directly from the thalamus to the amygdala and can automatically trigger physical and behavioural fear responses to prevent humans from getting injured. The purpose of this study was to investigate if there were any autonomic responses to stimuli containing positive valence and a high arousal level. The stimuli were normative pictures, picked from the IAPS that were presented subliminally in a masked condition. Reactions were measured by skin conductance responses. Changes of SCR were registered when the participants were exposed to negative, positive and neutral stimuli. Responses were strongest as the participants were exposed to the positive pictures. These findings support that there could be more functions to automatic responding than a direct survival purpose. Further research needs to be done to investigate what functions these kinds of responses constitute.
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Luoto, M. (Markus). "Managing control information in autonomic wireless networking." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526216454.
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Abstract As mobile Internet access traffic continues to grow at an explosive rate and wireless networks continue to diverge into multiple access technologies with partly overlapping sets of features, new solutions for efficient use of these networks are vital. Cognitive network management provides tools to tackle this challenge by automatically learning from past experience the characteristics and usage patterns of the connected devices, thus enabling autonomic optimization of those connections. Cognitive network management requires a vast amount of information in order to function effectively, making collaboration of the networked devices essential as the best sources of information are scattered throughout the network. This makes efficient information dissemination one of the key enablers for autonomic networking. This dissertation studies managing control information related to autonomic selection of access networks and adapting services in a heterogeneous wireless network environment. It presents a solution to simple and efficient information dissemination in the form of Distributed Decision Engine— a CEP-like system enabling the building of a highly scalable and dynamic messaging system enabling dissemination, analysis and control of the complex series of interrelated events in the network. The dissertation also presents results showing a clear benefit in using cross-layer and cross-domain information in a modern wireless environment and validates the final prototype implementation of DDE with laboratory measurements. Effective use of disseminated cross-layer information is another key element in autonomic wireless networking. This dissertation also focuses on intelligent decision-making based on cross-layer information by presenting test results which attest that the performance of an autonomic wireless networking system can be improved by using cognitive techniques in its management algorithms, and that hierarchy and coordination can be utilized to minimize the effect of conflicting decisions of the systemTiivistelmä Mobiilin Internet-liikenteen räjähdysmäinen kasvu ja langattomien verkkojen jatkuva jakautuminen useisiin tekniikoihin vaativat uusia ratkaisuja näiden verkkojen tehokkaaseen käyttöön. Kognitiivinen verkon hallinta mahdollistaa oppimisen, minkä avulla laitteiden yhteyksiä voidaan optimoida autonomisesti aiemman kokemuksen perusteella. Tällainen optimointi vaatii kuitenkin valtavan määrän verkosta ja laitteista kerättyä tietoa, mikä tekee tehokkaasta tiedonjakelusta keskeisen elementin autonomisessa verkon hallinnassa. Tässä väitöskirjassa tutkitaan verkon valintaan ja palveluiden sopeuttamiseen vaadittavan tiedon välittämistä ja hallintaa autonomisissa langattomissa verkoissa. Ratkaisuna yksinkertaiseen ja tehokkaaseen tiedonvälitykseen esitellään hajautettu Distributed Decision Engine -komponentti, joka mahdollistaa skaalautuvan tiedon jakelu-, analysointi- ja hallintajärjestelmän rakentamisen. Lisäksi väitöskirjassa kuvataan myös tuloksia, jotka osoittavat, että verkkokerrosten välisen tiedon käyttämisellä voidaan saavuttaa selvää etua, sekä tuloksia, jotka vahvistavat DDE-prototyyppitoteutuksen toimivuuden laboratoriomittauksin. Verkkokerrosten välisen tiedon tehokas hyödyntäminen on toinen keskeinen tekijä autonomisessa langattomien verkkojen hallinnassa. Väitöskirjassa käsitellään myös älykästä päätöksentekoa kyseisen informaation pohjalta sekä esitellään tuloksia, jotka osoittavat, että päätöksentekoa autonomisessa langattomien verkkojen hallinnassa voidaan parantaa kognitiivisilla tekniikoilla. Lisäksi esitetyt tulokset osoittavat, että hierarkialla sekä koordinoinnilla voidaan minimoida ristiriitaisten päätösten vaikutukset järjestelmään
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Esmaili, Ehsan, and Ehsan Esmaili. "Scalable Autonomic Management of 3D Cardiac Simulations." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/625913.
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Chronic Heart Failure (CHF) affects millions of Americans each year and it is the leading cause of hospitalization of the patients over the age of 65. The 3D cardiac simulation based on the bidomain model play an important role in understanding the CHF by simulating the interactions between the tissue cells. However, the computation complexity of the cardiac models has led cardiac researchers to less accurate models that are computationally tractable. In this thesis, we propose algorithmic and Graphics Processing Unit (GPU) specific optimizations to significantly reduce the amount and the complexity of computations needed for solving the bidmoain model. We propose a data reduction strategy and 2D cut based workload partitioning strategy to minimize the data transfer overhead and achieve strong scalability when executing the simulations on a multi-GPU environment. We propose an autonomic management framework based on the physics aware programming (PAP) paradigm for accelerating the cardiac simulations of monodomain model further beyond what can be achieved through traditional parallelization efforts. We apply machine learning techniques to detect the phase of the simulation during each time step of the 3D model of a human cardiac simulation. We dynamically change the resolution of the simulation based on the detected phase, and adjust the numerical solvers to optimize performance without sacrificing the accuracy of the simulation. We show that the scalable, algorithmically optimized and PAP-based implementation of bidomain model on 16 GPUs reduces the execution time of the 3D cardiac simulations by a factor of 128 and 145124 compared to the state-of-the-art multi-GPU (on 16 GPUs) implementation and CPU-based serial implementation respectively based on tissue size of 256×256×256 with a simulation accuracy of 99.9%. This drastic reduction in simulation time will allow clinicians to accurately identify the CHF patients prone to ventricular arrhythmias, rapidly evaluate and develop therapy options, and perform interactive cardiac analysis without the risk of the invasive procedure.
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Clark, Charles V. "Autonomic nerve function in the primary glaucomas." Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/23794.
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Shan, Jing. "Adrenomedullin regulates neuroendocrine and central autonomic functions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0013/MQ59876.pdf.
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Fuad, Mohammad Muztaba. "An autonomic software architecture for distributed applications." Diss., Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/fuad/FuadM0807.pdf.
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Olgart, Caroline. "Studies on nitric oxide in autonomic neurotransmission /." Stockholm, 1998. http://diss.kib.ki.se/1998/91-628-2961-0.
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Lehoux, Cory Paul. "Sensory and autonomic function in subclinical depression." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=96771.
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Depression is among the most common psychiatric disorders and is associated with significant disability, including pain, physical dysfunction, and a number of serious medical conditions. The pathophysiological mechanisms underlying this relationship are unclear, but are thought to involve dysfunction of the stress system. This thesis explores sensory and stress function in young adults with subclinical low mood – i.e. below the threshold for a clinical depressive disorder – and normal mood controls. Pain and somatic problems were frequent in men and women with depressive symptoms, despite the fact that their pain thresholds were normal. This suggests that their aches and pains were not the result of generalized hypersensitivity. The inflammatory response induced by capsaicin was significantly reduced in low mood, indicating impaired function, or even loss, of small-diameter afferent fibres in the superficial layers of the skin. Function of the autonomic system was also abnormal in subclinical depression. Heart rate variability at rest was lower, reflecting a shift in sympathovagal balance characterized by decreased vagal and/or increased sympathetic tone. The response to a mild stressor was similarly abnormal, but increased autonomic reactivity to stress was more strongly associated with anxiety than depression scores. The peripheral sympathetic vasoconstriction reflex was intact in low mood subjects, with an increased vasoconstrictive response in low mood women, but not men, suggesting sympathetic hyperreactivity. The data imply that, like clinical depression, subclinical low mood is not a benign condition, but is associated with impaired health, pain and somatic complaints, and sensory dysfunction in apparently healthy young adults. The autonomic dysfunction is similar to that observed in clinical populations, and it provides a plausible explanation for the sensory and somatic problems.La dépression est un des troubles psychiatriques les plus communs et est associée avec des incapacités significatives, telles la douleur, un dysfonctionnement physique, et un nombre de conditions médicales sérieuses. Les mécanismes pathophysiologiques sous-jacents cette association ne sont pas bien compris, mais semblent impliquer le système du stress. Cette thèse explore le fonctionnement des systèmes sensoriel et du stress chez de jeunes adultes avec une humeur dépressive sous-clinique – c'est-à-dire sous le seuil de la dépression majeure – et des participants contrôles ayant une humeur normale. La douleur et les problèmes somatiques sont fréquents chez les hommes et les femmes ayant des symptômes dépressifs, malgré le fait que leur seuil de la douleur soit normal. Ceci suggère que leurs maux et douleurs ne sont pas le résultat d'une hypersensibilité généralisée. La réponse inflammatoire induite par la capsaïcine était réduite de façon significative chez les participants à l'humeur basse, suggérant un fonctionnement détérioré, ou même, une perte de fibres afférentes à petit diamètre dans les couches superficielles de la peau. Le fonctionnement du système nerveux autonome était aussi anormal dans la dépression sous-clinique. La variabilité du rythme cardiaque au repos était plus basse, reflétant un changement dans la balance sympathovagale, caractérisé par une activité vagale réduite et/ou une activité sympathique augmentée. La réponse à un stress mineur était similairement anormale, mais l'augmentation de la réactivité autonome au stress était plus fortement associée aux symptômes anxieux que dépressifs. Le réflexe vasoconstricteur sympathique était intact chez les participants à l'humeur basse, mais une augmentation de la réponse vasoconstrictrice chez les femmes à l'humeur basse, mais pas les hommes, suggère une hyperréactivité sympathique. Les données impliquent que, comme lors d'une dépression majeure, une humeur basse sous-clinique n'est pas une condition bénigne, mais est associée avec une santé détériorée, des plaintes somatiques, de la douleur, et un dysfonctionnement sensoriel chez des adultes en apparence en bonne santé. Le dysfonctionnement du système autonome est similaire à ce qui a été observé dans les populations cliniques, et il fournit une explication plausible aux problèmes sensoriels et somatiques.
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陸靜妍 and Jingyan Lu. "Emotional intelligence and stress related autonomic activity." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B42575308.
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Zarneh, A. T. "Instrumentation for on-line autonomic function testing." Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371492.
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