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In this thesis, we study the neurocomputation by implementing two different neuron models. One is a semi magnetic micro p-n wire that emulates nerve fibres and supports the electrical propagation and regeneration. The other is a silicon neuron based on Hodgkin-Huxley conductance model that can generate spatiotemporal spiking patterns. The former model focuses on the spatial propagation of electrical pulses along a transmission line and presents the thesis that action potentials may be represented by solitary waves. The later model focuses on the dynamical properties such as how the output patterns of the active networks adapt to external stimulus. To demonstrate the dynamical properties of spiking networks, we present a central pattern generator (CPG) network with winnerless competition architecture. The CPG consists of three silicon neurons which are connected via reciprocally inhibitory synapses. The network of three neurons was stimulated with current steps possessing different time delays and that the voltage oscillations of the three neurons were recorded as a function of the strengths of inhibitory synaptic interconnections and internal parameters of neurons, such as voltage thresholds, time delays, etc. The architecture of the network is robust and sensitively depends on the stimulus. Stimulus dependent rhythms can be generated by the CPG network. The stimulus-dependent sequential switching between collective modes of oscillations in the network can explain the fundamental contradiction between sensitivity and robustness to external stimulus and the mechanism of pattern memorization. We successfully apply the CPG in modulating the heart rate of animal models (rats). The CPG was stimulated with respiratory signals and generated tri-phasic patterns corresponding to the respiratory cycles. The tri-phasic stimulus from the CPG was used to synchronize the heart rate with respiration. In this way, we artificially induce the respiratory sinus arrhythmia (RSA), which refers to the heart rate fluctuation in synchrony with respiration. RSA is lost in heart failure. Our CPG paves to way to novel medical devices that can provide a therapy for heart failure.

O objetivo deste trabalho é a investigação de um algoritmo adaptativo para compensação dos erros no cálculo dos fasores do sistema de potência quando há variações significativas na freqüência dos sinais de tensão e corrente. O principal benefício desta técnica é permitir a compensação dos erros utilizando freqüência de amostragem e janela de dados constantes, possibilitando a construção de relés microprocessados para proteção de geradores com hardware mais simples. O algoritmo adaptativo denominado AIVF (Algoritmo Inume a Variações de Freqüência) foi testado a partir de uma série de sinais com características como variação da freqüência da fundamental, componente exponencial amortecida e harmônicos, sendo os resultados apresentados no capítulo 4.4. Além do AIVF, nos capítulos iniciais são apresentados aspectos inerentes à proteção de geradores como aterramento e uma descrição das principais proteções aplicáveis a geradores de até 50MVA. / The main pourpose of that work is inquire an adaptive algorithm to compensate the errors in the power system phasors calculation when occur significant changes in the frequency of the current and voltage signals. The main benefit of that technique is to permit errors compensation with constant sampling frequency and constant data window, making possible construction of microcomputer relays for generator protection with simple hardware. The adaptive algorithm named ANAFC (Algorithm Not Affected by Frequency Changes) was tested by some signals with characteristics like changes in the fundamental frequency, dc decaying and harmonics. The results are presented in the section 4.4. Beyond ANAFC, in the initial sections are presented aspects regarding generator protection like earthing and a description of the main protection functions applied in generators till 50MVA.

Movement is controlled by neuronal central pattern generator (CPG) networks that are segmentally organised in organisms across the animal kingdom. The precise role of neuromodulators in the function, development and, particularly, the maintenance of these circuits is currently unresolved. This study investigates the effects of chronically altered signalling of tyramine and/or octopamine, two well established neuromodulators, in Drosophila larval locomotion. It shows that tyramine reduces crawling speed in larvae, whereas octopamine increases speed up to a physiological maximum. Changes in crawling speed are mediated by modulating stride duration, whilst stride length remains constant. These two neuromodulators also affect segmental muscle contraction and relaxation rates, indicative that the effects on crawling speed are likely to be at least partially due to modulatory effects on muscle physiology. Muscle recordings from muscle M6 in two adjacent segments, during fictive forward locomotion show that stride duration is influenced by a variable time delay between segmental CPG outputs. Frequency and duration of individual segmental outputs, by contrast, remains constant. The behavioural and electrophysiological data suggest, therefore, that the segmental locomotor CPG outputs remain constant in response to chronically altered neuromodulatory signalling. This study also identified a close spatial proximity of motor neuronal dendritic branches and putatively octopaminergic and/or tyraminergic synaptic terminal varicosities in the ventral nerve cord (VNC) neuropil. Moreover, manipulation of a putatively octopaminergic and/or tyraminergic subpopulation of interneurons, located in anterior brain regions, is sufficient to induce a similar, albeit smaller, larval crawling deficit. This indicates that the effects of locomotion may be induced in the central nervous system. This is confirmed in identified motor neurons as chronic changes in octopaminergic and/or tyraminergic signalling increase the frequency of bursting of action potential firing. In addition, the synaptic current amplitudes are substantially reduced in both ventral and dorsal muscle- innervating motor neurons, indicative of an effect to presynaptic excitation. In contrast, the function of neuromuscular junction remains largely unchanged. Taken together, this data shows that neuromodulation is sufficient to alter the output of a relatively small group of neurons, that comprise the locomotor CPG. The site of action of these modulators is, however, likely to be diverse.

One of the major difficulties in web application design is the tediousness of constructing new web pages from scratch. For traditional web application projects, the web application designers usually design and implement web application projects step by step, in detail. My project is called “automatic generation of web applications and management system.” This web application generator can generate the generic and customized web applications based on software engineering theories. The flow driven methodology will be used to drive the project by Business Process Model Notation (BPMN). Modules of the project are: database, web server, HTML page, functionality, financial analysis model, customer, and BPMN. The BPMN is the most important section of this entire project, due to the BPMN flow engine that most of the work and data flow depends on the engine. There are two ways to deal with the project. One way is to go to the main page, then to choose one web app template, and click the generating button. The other way is for the customers to request special orders. The project then will give suitable software development methodologies to follow up. After a software development life cycle, customers will receive their required product.

<p>In this thesis, a Static Random Access Memory generator has been designed and implemented. The tool can generate memories of different sizes. The number of words that can be stored can be chosen among powers of 2 and the number of bits per word can be up to 48. </p><p>The focus of the thesis was to find an adequate structure for the generated memories depending on the size, and develop a memory generator that implements the structures, which has been thoroughly done. The single circuits used in the generated memories can be substituted with better circuits as well as adapted to other processes. </p><p>All circuits apart from a block decoder circuit have been developed. The memory generator was not supposed to automatically produce a complete layout, and some manual interventions on the memories generated by the tool are necessary. The tool requires to be developed further to minimise this manual intervention on the generated memories. The complete memories generated have not been tested because of their complexity, but tests on circuits as well as many parts of the memories have been carried out. </p><p>During the thesis work, a large amount of tasks had to be carried out and a lot of issues had to be dealt with, which has been a problem. The tool used for the implementation has powerful features for both analog and digital electronic design, but has stability problems with large designs, which has been a big obstacle in this work.</p>

<p>A new, template-based code generator has been implemented for the OpenModelica compiler. All data needed for target code generation has been collected in a new data structure that is then sent to templates which generate target code based on that data. This simplifies the implementation of the code generator and also makes it possible to write a different set of templates to generate target code in a different language.</p><p>The new, template-based code generator currently only supports generation of target code for simulating Modelica models. In that scenario it translates models roughly at the same speed as the old code generator.</p>

<p>In this thesis, a concept for a modular assembly direct drive permanent magnetgenerator is presented. The maximum forces that act on the different parts of thegenerator during normal operation have been calculated and used in solid mechanicsimulations in SolidWorks. The result is a rough first draft of a generator designwhere the stator has been divided into five modules and the rotor into six modules.This division is done in order to avoid symmetries in the generator that could lead toproblems with self-oscillation.The modulization of the stator brings about certain difficulties, both for the magneticcircuit and for the winding scheme. Different solutions for optimization of themagnetic circuit are analyzed from both a physical and a construction technicalperspective. A winding scheme is produced and the winding process tested in awinding dummy produced according to the conceptual generator design.</p>

<p>Harmonics are a well-known problem that has to be dealt with in the design of thegenerator. Internationally accepted standards limits the amount of harmonics allowedin the no-load voltage. These limits can be difficult to fulfill with integral slot winding,where the number of slots per pole and phase is an integer. The presence of thedamper winding often makes the problem with harmonics even worse and harmonicswith frequencies of order 6q±1 arise with significant amplitude. How the damperwinding is designed affect the content of harmonics in the no-load voltage and the aimwith these … has been to investigate in which extent design of the damper windingaffects the contents of harmonics.Simulations with the 2-D finite element method have showed that if the damper barsis centered in the pole shoe, the amplitude of the harmonics of order 6q±1dependsboth on the ratio between the stator slot pitch and damper bars slot pitch and if thedamper bars are connected between the poles or not.If the damper bars is displaced with ¼ stator slot pitch alternately, the amplitude ofthe harmonics of order 6q±1 is reduced and the influence of the ratio between thestator slot pitch and the damper bars slot pitch will vanish. To minimize the loss inthe damper bars the distance between the damper bars should then be equal thedistance between the stator slots.</p>

In individuals with spinal cord injury (SCI) who have disrupted communication between the brain and spinal cord, vibration may mimic functions formerly served by the lost or impaired supraspinal inputs resulting in more normal reflex modulation and improved walking function. Three experiments assessed the effects of vibration on spinal locomotor-generating circuitry, spinal reflex activity, and walking function. In Experiment 1, localized leg vibration was used to elicit air-stepping responses in the lower extremities. We compared responses of individuals with SCI to those of non-disabled (ND) individuals and assessed the influence of severity injury and locomotor training on the air-stepping response in individuals with SCI. Our results indicate that vibration of the tensor fascia latae elicited more consistent and robust responses than vibration of the quadriceps or hamstrings muscles. Individuals with SCI had less consistent and robust responses than ND individuals. In those with SCI, neither severity of injury nor locomotor training influenced the robustness or consistency of the response. In Experiment 2, we investigated the effect of whole-body vibration (WBV) on spasticity, as measured by spinal stretch reflex (SSR) excitability, in individuals with SCI. We also assessed differences in the influence of WBV among individuals who used antispastic medications and those who did not. Subjects were tested before and after participation in a 3 day/week, 12-session WBV intervention. There was a significant reduction in spasticity that persisted for several days following the WBV intervention. The amount by which spasticity was reduced was not different in those who used antispastic agents compared to those who did not use these agents. In Experiment 3, we assessed the effects of the 12-session WBV intervention on walking function. WBV was associated with significant increases in walking speed, cadence, step length of the stronger leg, and consistency of hip-knee intralimb coordination. Increases in cadence and stronger-leg step length correlated with improvements in walking speed. These results suggest that WBV may represent an approach to decreasing spasticity, and may be useful for individuals in whom spasticity interferes with function. Furthermore, vibration appears to have a beneficial effect on walking function, perhaps by influencing spinal locomotor-generating circuitry.