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1
De, la Cruz Miguel. "The influence of transient thermo-elastohydrodynamic conjunctions on automotive transmission rattle." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8042.
Abstract:
Automotive transmission rattle is the noise generated due to impacts between manual transmissions meshing gear teeth in the presence of backlash. It is considered to be a Noise, Vibration and Harshness (NVH) phenomenon and is originated due to combustion irregularities (engine order vibrations), especially in diesel vehicles. This thesis focuses in the case of creep rattle for the MMT6 Ford Getrag transmission (six speeds plus reverse) with a DW10b, 4-cylinder, 4-stroke, 2.0 litres diesel engine. This particular rattle condition is fundamentally similar to any other where an engaged gear is pertained (drive, over-run or float), with the 1st or 2nd gear engaged at a very low engine speed. The numerical models include an initial single degree of freedom (DoF) simulation. It comprises either of the engaged gear pair under Hertzian contact conditions or of a loose gear pair under hydrodynamic regime of lubrication. Once the validity of this model is established and correlated with the results obtained from a single gear pair test rig, simulations of increasing complexity can be envisaged. A 7 DoF numerical model is, therefore, developed. The Hertzian contact model still prevails for the engaged gear pair, whereas an analytical hydrodynamic solution is implemented for the remaining 6 loose gear wheels and Petrov s law is applied to the needle bearings retaining the gear wheels. With the aim of accommodating a fully lubricated model of all the tribological conjunctions, an analytical elastohydrodynamic (EHL) Grubin type algorithm is employed. Also, the energy equation is analytically solved for hydrodynamic and elastohydrodynamic conjunctions, based on the assumptions dictated by the Peclet number. Therefore, under hydrodynamic conditions, the energy equation is governed by viscous heating and convective cooling, whereas in the EHL conjunctions the governing terms are viscous and compressive heating, together with conductive cooling. The retaining needle bearings follow the same heat generation mechanism as journal bearings. The effective viscosity, as obtained from the Houpert s equation accounting for pressure and thermal effects, is fundamental for the study of the friction in the contact. The hydrodynamic contacts are only governed by viscous friction, whereas EHL conjunctions exhibit asperity iv interactions as well as viscous effects. The results obtained from this new 7 DoF model are then compared to the experimental measurements taken from the vehicle tests and various purpose-built drivetrain rigs. A metric named Impulsion Ratio is hereby introduced, aiming to shed some light into the predictions obtained by the various models presented. This metric is the ratio of driving over resistive forces acting on each individual gear wheel. Its use is tested to predict single or double-sided rattle scenarios and, therefore, ascertaining higher and lower rattle levels. The 13 DoF model from which these conclusions were obtained includes shafts planar translation and rocking moments. The rolling element bearings supporting the shafts are, therefore, modelled to capture the inherent frequencies arising from their motion. The final model introduces the effects of transient thermo-elastohydrodynamics. This 7 DoF dynamic model accounts for a numerical solution of Reynolds equation with Elrod s cavitation algorithm for simultaneous teeth in mesh. The results obtained validate the previously used Grubin assumption by comparing the predicted central film thickness along the full mesh of one tooth. Also, the effect of starved input conditions and thermal and isothermal solutions are studied.
2
Cantalogo, Alexsander. "Modelagem de \'Deadeners\' usando NASTRAN e correlação experimental." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-13032012-085537/.
Abstract:
Este trabalho visa o desenvolvimento de um modelo em elementos finitos de elementos de dissipação vibratória de base betuminosa, chamados comumente de deadeners. O modelo baseia-se no algoritmo comercial MSC/NASTRAN e é correlacionado e verificado com base em dados experimentais de laboratório. O resultado final deste projeto é um modelo para os deadeners que pode ser utilizado em modelos de elementos finitos de veículos completos, facilitando assim a definição da melhor localização dos mesmos no veículo bem como a otimização de seu uso. O modelo tem melhor resultado em termos de amplitude para frequências abaixo de 200Hz, porém apresenta tendências de superestimar o efeito do amortecimento nos picos de ressonânciaThis project aims the development of a finite element model of vibration dissipating elements of bituminous base, commonly called \"deadeners. The proposed model is based on the finite element commercial algorithm MSC/NASTRAN and is correlated and verified on experimental data from laboratory. The end result of this project is a model for \"deadeners\" which can be used in finite element models of complete vehicles, thus facilitating better definition of their location in the vehicle as well as the optimization of its use. The model has a better result in terms of amplitude for frequencies below 200 Hz, but shows a tendency to overestimate the effects of damping at the resonance peaks
3
Souza, Fernando José Pires de [UNESP]. "Eficácia de uma vacina comercial contra a raiva frente a desafios com amostras de vírus de campo comparados ao desafio padrão no teste NIH." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/94645.
Abstract:
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No Brasil, a potência das vacinas veterinárias contra a raiva é avaliada pelo teste NIH (“National Institutes of Health”), no qual o desempenho de uma vacina, medido pela DE50 em camundongos, é comparado ao desempenho de uma vacina de referência. São consideradas aprovadas as partidas com potência igual ou superior a 1,0 UI. O presente estudo comparou o desafio viral com vírus fixo CVS, utilizado como padrão no teste de potência NIH, a desafios com três amostras virais isoladas de bovinos naturalmente infectados. O objetivo foi verificar se as amostras de vírus de campo apresentariam virulência maior que a do CVS, o que poderia sugerir a inadequação do teste NIH para a avaliação das vacinas contra a raiva e, portanto, inferir que as vacinas aprovadas por esse teste poderiam não proteger suficientemente o rebanho. Apesar da grande variabilidade que o teste NIH pode apresentar, as três repetições desafiadas com CVS apresentaram semelhança em um intervalo de confiança de 95%, e nos desafios realizados com três amostras de vírus de campo a vacina utilizada protegeu mais do que nos desafios com CVS. Conclui-se que a virulência das amostras de vírus de campo utilizadas não foi maior que a virulência do CVS, em camundongos, e que o rigor do desafio padrão mostrou-se adequado para a avaliação da potência pelo teste NIH e, portanto, para o controle da qualidade de vacinas contra a raiva.
The potency of veterinary rabies vaccines in Brazil is evaluated by the NIH (National Institutes of Health) potency test, in which the ability of a vaccine to induce protection in mice (ED50) is compared with a reference vaccine. The batches are approved when the potency is equal or superior to 1.0 IU. The present study compared CVS strain challenges (standard strain for the potency test) with challenges that used three wild isolates of natural occurrence in cattle. The aim was to verify if the wild strains could be more virulent than the CVS. If this occurred, the NIH potency test would prove inadequate to evaluate rabies vaccines. Therefore, one could infer that the approved vaccines might not provide sufficient herd protection. Despite the great variability of NIH test, all three repetitions that were challenged with CVS were similar at a 95% confidence-level; and when challenged with wild strains, the vaccine provided better protection than the one achieved at CVS challenge. In conclusion, wild strains virulence was not greater than CVS virulence in mice. The strictness of standard challenge proved to be adequate for potency evaluation by NIH test, and consequently, for the quality control evaluation of rabies vaccines.
4
Park, Hyungjoo. "Development of a Test System to Measure Squeak Propensity of Vehicle Underbody Components." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592135515122287.
5
Xie, Yuan. "Investigation on Road Noise Transmission through Steering System." Thesis, KTH, MWL Marcus Wallenberg Laboratoriet, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-224153.
Abstract:
An investigation on noise transmission through the steering gear system is focused on the area of vehicle NVH (Noise Vibration and Harshness). From previous investigations it is well known that noise transmission through the steering system sometimes has a significant influence referring to tire road noise. In these cases, the interface force between steering gear and vehicle subframe is usually of interest during early stages of vehicle development. The target of the current work is to validate an approach based on a method, commonly known as the “Blocked force method” for noise and vibration testing, and check if it is possible to estimate the interface forces based on this method. This method became popular for mechanical testing in the middle 1900s [1] [2] [3], because of its easy applicability. The basic idea is to fix the component on a rigid plate and measure the interface force at the coupling points with force transducers inserted in between. It has a considerable potential in practical use, because if the blocked force could provide a good estimation for the interface force in noise transmission, it enables an efficient measurement of critical NVH behaviors without having to resort to the complete vehicle.However intuitively, the blocked force data could not be used directly. As a result, a coupled system equation is used for the coupling of the steering gear and the car body. Both the inertance of car body and steering system are taken into account, and thus introduces a compensation for the difference between vehicle and test bench. The method is validated against the transfer function measured on the full vehicle as the reference and compare this with the result calculated with the measured “Blocked force” data. Siemens Test.Lab is used for data acquisition and first data processing. Matlab is used for data post processing. Matrix symmetrization and singular value truncation is used to deal with the ill-conditioned data of steering gear inertance. A hybrid model with Finite Element data is proposed. Two test conditions are investigated: one set is with rigid coupling and the other is decoupled with rubber.
6
FERRARIS, ALESSANDRO. "Automotive composite components design and test: a vibration reduction oriented approach." Doctoral thesis, Politecnico di Torino, 2017. http://hdl.handle.net/11583/2674339.
Abstract:
Vehicle manufacturers initially relied on horsepower and speed performances as “standout qualities” to sell their products, but as time progressed, it became increasingly clear that customers were very much concerned about their comfort and safety while driving vehicles. In the late seventies, requirements for driver and passenger comfort were increased significantly, since-then, a large amount of effort has been invested into the vehicle improvement of noise and vibration reduction nevertheless enhancing the safety.
Nowadays NVH performance is considered as a critical factor in the purchase decisions of many buyers. This work focusses on the development of a composite automotive door but, the methodology and materials applied could be extended for other panels, as there are several kinds in a typical vehicle whatever class or purpose it has. In the last years, furthermore, lightweight design imposed different design methodologies and materials like fiber reinforced plastics are becoming more and more used in the construction of vehicles for structural and non-structural parts.
Reinforced plastics could perform higher performance and higher tailorable possibilities compared to conventional metallic materials, more and more composites are targeted toward structural applications involving combined dynamic, mechanical, thermal and hygral loading. Composite materials are principally preferred in such applications because of their advanced elastic properties and tailoring capability to individual design requirements. They also have the potential for incorporating significant and tailorable passive damping into the candidate structure.
At the beginning, tests on two different viscoelastic materials are performed in order to identify mechanical characteristics necessary to provide valid data for numerical analysis of structures. ‘Oberst Beam Method’ is the standard test method for measuring dynamic properties of materials (ASTM E756 – 05). Mechanical characteristics of damping materials have been determined for different temperatures (SAE J1637), frequencies and at different stage of aging (ISO 60068). Besides, low-velocity impact tests have been executed (ASTM 7136). After having post-processed the experimental data, the best material has been chosen. For each test, for each material and specimens topology a significant number of specimen has been tested for statistical purpose. ASTM 756 tests have been replicated virtually and to compare the results FRF Receptance, eigenfrequencies have been matched. Excellent correlation between simulation and experiment has been found. To evaluate the FEM virtual capabilities to reproduce and simulate the dynamic response of a real component and to validate correlation methodology, a first modal analysis has been carried out on a real automotive component. An innovative composite leaf spring is subjected to a free-free frequency response test, in which a series of accelerometers measures the response of the component to an excitation imposed by an electromechanical shaker. Moreover, LIPEZ methodology permitted to post-process data logged and to evaluate the characteristic vibrating modes of the structure. While the real component has been experimentally tested, FEM numerical simulation is reproduced. In the end, eigenfrequencies, eigenmodes (MAC) of experimental and virtual tests have been compared; excellent mode shape correlation has been found-out, errors on eigenfrequencies lower than 5%. Last part of this dissertation is focussed on the design, testing, and development of a damped door by means of interlaminar materials. The activity has been performed in two stages: undamped door testing and correlation with FEM and then manufacturing, testing and correlation of the damped solution. LIPEZ modal extraction algorithm has been used to extract modal parameters for the two artifacts, as well. The undamped door has been tested, real and virtual receptance, eigenfrequencies, eigenmodes computed and correlated. Damped material patches have been dimensioned and positioned considering a trade-off between added mass, costs and vibro-reduction capabilities. Modal analysis executed on the door have demonstrated that high damping capabilities have been achieved with limited drawbacks on weight increase (+5%) and inappreciable cost augmentation.
In view of the scopes of the work, the results are deemed satisfactory.
7
Otipka, Václav. "Konstrukční návrh zkušebního stavu s uzavřenou smyčkou toku momentu pro experimentální ověření parametrů převodových ústrojí." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-378013.
Abstract:
The thesis deals with the design of the experimental testing rig. Test rig is designed to measure NVH transmission parameters. First, basic knowledge of vibro-acoustic measurement is discussed. This is followed by an evaluation of the most commonly used power devices to derive real loads on measured gearboxes. In more detail, a back-to-back test rig is disassembled among other things. In the thesis are described two main components, which are composed of a connecting element and a test bench. Both components were optimized during the design due to their modal properties. Numerical modal analysis was performed in ANSYS Workbench software. The thesis also includes strength calculations performed using both numerical and analytical approaches. The indispensable result of the design work is the complete drawing documentation. Finally, measurements of vibrations and noise on the physically made connecting element assembly have been performed and subsequently evaluated.
8
Baker, Erin R. "Attitudes and Practices of NIH-funded Researchers Toward Reporting Individual Test Results to Research Subjects." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1147100909.
9
Schille, Fabian Martin [Verfasser], and A. [Akademischer Betreuer] Albers. "Methode zur generationsübergreifenden NVH-Optimierung des Wiederstartkomforts von Hybridfahrzeugen durch eine manöverbasierte Validierung auf dem Akustikrollenprüfstand = Method for an intergenerational NVH-optimisation regarding the restarting comfort of hybrid vehicles using a manoeuvre-based validation on the acoustic roller test bench / Fabian Martin Schille ; Betreuer: A. Albers." Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1235072436/34.
10
Virhammar, Johan. "Idiopathic Normal Pressure Hydrocephalus : Cerebrospinal Fluid Tap Test and Magnetic Resonance Imaging as Preoperative Prognostic Investigations." Doctoral thesis, Uppsala universitet, Neurologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-222779.
Abstract:
Idiopathic normal pressure hydrocephalus (iNPH) is a condition with dilated cerebral ventricles but intracranial pressure within normal limits. The symptoms of gait impairment, cognitive decline and urinary incontinence develop gradually. Treatment with shunt insertion results in improvement in eight out of ten patients. The cerebrospinal fluid tap test (CSF TT) and preoperative magnetic resonance imaging (MRI) are methods used to select patients who may benefit from shunt surgery, but they are performed and interpreted differently in different centers throughout the world. The aim of this thesis was to evaluate the performance of the CSF TT and the underlying mechanisms of improvement in gait function after CSF removal, and to investigate the prognostic value of preoperative MRI scans. Improvement in gait and changes in cerebral blood flow (CBF) after a CSF TT were investigated in two prospective studies that included 39 and 20 patients, respectively. Gait assessment and perfusion MRI were done before and several times during the first 24 hours after a CSF TT. Perfusion was investigated with pseudo-continuous arterial spin labeling. At the group level, gait function was significantly improved at all investigation times, but only one-third of individual CSF TT responders were improved at all investigation times. In patients with increased CBF in lateral and frontal white matter after the CSF TT, gait function improved more than it did in patients with decreased CBF in these regions. However, in the whole sample, there was no significant increase in CBF after CSF removal. Preoperative MRI scans were retrospectively evaluated in 109 patients with iNPH who had undergone shunt surgery. The callosal angle was smaller in shunt responders compared with non-responders. The following findings showed the highest association with a positive outcome after shunting: a small callosal angle, wide temporal horns, and occurrence of disproportionally enlarged subarachnoid space hydrocephalus. In conclusion, CBF in white matter close to the lateral ventricles may play a role in the reversibility of symptoms after CSF removal in patients with iNPH. The CSF TT should be reevaluated if the patient does not initially improve, and preoperative MRI investigations can add prognostic information regarding the selection of shunt candidates.
11
Souza, Fernando José Pires de. "Eficácia de uma vacina comercial contra a raiva frente a desafios com amostras de vírus de campo comparados ao desafio padrão no teste NIH /." Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/94645.
Abstract:
Orientadora: Adolorata Aparecida Bianco CarvalhoBanca: Maria da Gloria Buzinaro
Banca: Luzia Helena Queiroz
Resumo: No Brasil, a potência das vacinas veterinárias contra a raiva é avaliada pelo teste NIH ("National Institutes of Health"), no qual o desempenho de uma vacina, medido pela DE50 em camundongos, é comparado ao desempenho de uma vacina de referência. São consideradas aprovadas as partidas com potência igual ou superior a 1,0 UI. O presente estudo comparou o desafio viral com vírus fixo CVS, utilizado como padrão no teste de potência NIH, a desafios com três amostras virais isoladas de bovinos naturalmente infectados. O objetivo foi verificar se as amostras de vírus de campo apresentariam virulência maior que a do CVS, o que poderia sugerir a inadequação do teste NIH para a avaliação das vacinas contra a raiva e, portanto, inferir que as vacinas aprovadas por esse teste poderiam não proteger suficientemente o rebanho. Apesar da grande variabilidade que o teste NIH pode apresentar, as três repetições desafiadas com CVS apresentaram semelhança em um intervalo de confiança de 95%, e nos desafios realizados com três amostras de vírus de campo a vacina utilizada protegeu mais do que nos desafios com CVS. Conclui-se que a virulência das amostras de vírus de campo utilizadas não foi maior que a virulência do CVS, em camundongos, e que o rigor do desafio padrão mostrou-se adequado para a avaliação da potência pelo teste NIH e, portanto, para o controle da qualidade de vacinas contra a raiva.
Abstract: The potency of veterinary rabies vaccines in Brazil is evaluated by the NIH (National Institutes of Health) potency test, in which the ability of a vaccine to induce protection in mice (ED50) is compared with a reference vaccine. The batches are approved when the potency is equal or superior to 1.0 IU. The present study compared CVS strain challenges (standard strain for the potency test) with challenges that used three wild isolates of natural occurrence in cattle. The aim was to verify if the wild strains could be more virulent than the CVS. If this occurred, the NIH potency test would prove inadequate to evaluate rabies vaccines. Therefore, one could infer that the approved vaccines might not provide sufficient herd protection. Despite the great variability of NIH test, all three repetitions that were challenged with CVS were similar at a 95% confidence-level; and when challenged with wild strains, the vaccine provided better protection than the one achieved at CVS challenge. In conclusion, wild strains virulence was not greater than CVS virulence in mice. The strictness of standard challenge proved to be adequate for potency evaluation by NIH test, and consequently, for the quality control evaluation of rabies vaccines.
Mestre
12
Reis, Danilo Bruneli. "Posicionamento de \"Deadeners\" para a redução de vibração em estruturas veiculares via sensibilidade inerente." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-21032018-153547/.
Abstract:
O desempenho acústico em um veículo é fortemente dependente da interação fluido-estrutura entre o ar no habitáculo do veículo e a estrutura metálica. A maioria dos problemas de ruído e vibração relacionados a esta interação provem dos picos de ressonância da chapa metálica, quando excitada por forças externas (pista, motor, vento). A redução dos picos de ressonância pode ser obtida através da aplicação de placas asfálticas (\"Deadeners\") na estrutura. O problema está no posicionamento das placas, que usualmente é realizado experimentalmente por tentativa e erro. Este trabalho propõe o uso da sensibilidade inerente para o posicionamento de \"Deadeners\" em estruturas metálicas veiculares, em particular no teto do veículo. As funções de resposta em freqüência (FRFs) do teto são obtidas experimentalmente e processadas adotando a técnica da sensibilidade inerente, obtendo assim a sensibilidade dos picos de ressonância e identificando os locais passíveis de instalação de \"Deadeners\". Como resultado da análise, é possivel localizar a posição ótima para o \"Deadener\" que maximizará a redução de picos de resonância de interesse. Após o posicionamento dos \"Deadeners\", foi possível verificar a atenuação dos picos de ressonância no teto do veículo, mostrando a eficácia do método utilizado. A maior vantagem do método é que este requer apenas medições de resposta em frequência do sistema original, sem necessidade de modificações na estrutura do veículo para obter a sensibilidade do sistema a modificações.The Noise Vibration and Harshness (NVH) performance of passenger vehicles strongly depends on the fluid-structure interaction between the air in the vehicle cavity and the sheet metal structure of the vehicle. Most of noise and vibration problems related to this interaction come from resonance peaks of the sheet metal, which are excited by external forces (road, engine, wind). A reduction of these resonance peaks can be achieved by applying deadeners in the sheet metal. The problem is where these deadeners shall be fixed, which is usually done in a trial-anderror basis. In this work, one proposes the use of embedded sensitivity to locate the deadeners in the sheet metal of the vehicle, more specifically in the vehicle roof. Experimental FRFs of the roof are obtained and data is processed by adopting the embedded sensitivity method, thus obtaining the sensitivity of the resonance peaks on the local increase of stiffness due to the deadeners. As a result, by examining the sensitivity functions, one can find the optimum location of the deadeners that maximize their effect in reducing the resonance peaks of interest. After locating the deadeners in the optimum positions, it was possible to verify a strong reduction in resonance peaks of the vehicle roof, thus showing the efficiency of the procedure. The main advantage of this procedure is that it only requires FRF measurements of the vehicle in its original state, not needing any previous modification of the vehicle structure to find the sensitivity functions.
13
Melo, Fábio Xavier de. "Análise de caminhos de transferência de energia no projeto de sistemas de controle." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-23092013-170034/.
Abstract:
A análise de caminhos de transferência de energia (TPA na sigla em inglês para Transfer Path Analysis) corresponde a um grupo de métodos numérico/experimental para análise e solução de problemas vibro-acústicos de sistemas lineares invariantes no tempo, sendo seu principal campo de aplicação a indústria automotiva. A TPA é uma técnica que identifica as principais fontes de vibração e ruído, e os caminhos estruturais e acústicos pelos quais são transmitidas para determinados locais de interesse. Conhecendo as fontes de ruído e vibração e os caminhos de propagação é possível propor modificações eficientes em minimizar o ruído/vibração nas regiões de interesse, ou atribuir características desejáveis para tais componentes, envolvendo técnicas de controle passivo e ativo. Este trabalho apresenta um estudo numérico e experimental das técnicas de TPA, utilizando métodos diretos e inversos de determinação de forças operacionais. Estes estudos foram realizados em um mockup de um veículo, com o objetivo de determinar o caminho de maior contribuição para o ruído no interior do protótipo, e a partir deste resultado, propor um sistema de controle ativo para minimizar este ruído interno.The Transfer Path Analysis (TPA) is a group of numerical/experimental tools for the analysis and troubleshooting of noise and vibration problems in linear time invariant vibroacoustic systems, being the automotive sector its major user. TPA consists of a numerical/experimental analysis that allows the identification of the main noise and vibration sources and the structural/acoustic transfer paths to the Target points. Based on the sources and paths, it is possible to propose modifications that efficiently minimize noise and vibration at the target positions. By means of active control it is possible to modify noise and vibration in order to change, rather than minimize noise and vibration, achieving certain design targets. This work presents a numerical and experimental study of TPA techniques, using direct and inverse operational loads determination methods. These studies were performed on a vehicle mockup, in order to determine the path of greatest contribution to the noise inside the prototype, and from this result, propose an active control system to minimize this internal noise.
14
Kossoski, Fábris. "Espalhamento elástico de elétrons por isômeros de C2H2CL2, C4H4N2 e C3H3NX (X=NH, O, S)." reponame:Repositório Institucional da UFPR, 2013. http://hdl.handle.net/1884/32790.
Abstract:
Resumo: Neste trabalho apresentamos seções de choque de espalhamento elástico de elétrons pelos isômeros C2H2Cl2, C4H4N2 e C3H3NX (onde X=NH, O, S). Os cálculos de espalhamento foram efetuados na aproximação de núcleos fixos, com uso do método multicanal de Schwinger implementado com pseudopotenciais de Bachelet, Hamann e Schl¨uter, e nas aproximações estático-troca e estático-troca mais polarização. Para os três isômeros C2H2Cl2 apresentamos seções de choque integrais, de trasferência de momento e diferenciais. O procedimento Born-closure é empregado a fim de levar em conta o efeito do momento de dipolo. As ressonâncias encontradas tiveram suas posições comparadas aos valores experimentais. Discutimos ainda o efeito isômero, que consiste em diferenças apresentadas pelas seções de choque de cada molécula. Para os três isômeros C4H4N2 apresentamos seções de choque integrais. As ressonâncias são identificadas e caracterizadas. Suas posições são comparadas com os resultados encontrados na literatura. Cálculos de estrutura eletrôncia também são efetuados para ajudar na interpretação dos resultados. Os seis sistemas C3H3NX, onde X=NH, O, S tiveram suas seções de choque integrais apresentadas. As ressonâncias são identificadas e comparadas ao resultado experimental existente. Também discutimos as diferenças nas características das ressonâncias de cada molécula. Para todos os sistemas estudados, nossos resultados concordam bem com os reportados experimentalmente. Foi desenvolvido ainda um novo esquema para a construção do espaço de configurações.
15
Warner, Sandra McCarthy. "Using GPS to Quantify Three Dimensional Storage and Aquifer Deformation in the Virgin River Valley, NV." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/9710.
Abstract:
The horizontal component of land subsidence is typically assumed to be negligible, although recently, theoretical simulations have shown that horizontal strain is significant. A field based investigation in Mesquite, NV, was undertaken from May to July, 2003, for the purpose of evaluating the significance of horizontal strain during an aquifer test. The hydraulic heads in the aquifer were monitored within a meter of the municipal pumping well used for the aquifer test and also at a distance of approximately 1,470 meters from the pumping well. Aquifer deformation in the horizontal and vertical directions were measured using GPS for the first 22 days of pumping in 10 different locations at radial distances from the well varying from 100 meters to 2500 meters. From 22 to 60 days of the aquifer test, the number of GPS stations monitoring deformation was reduced to five.
Radial displacement was measured at all monitoring stations during the aquifer test, indicating that the aquifer is moving closer to the pumping well. The greatest magnitude displacement measured 140 m from the well was approximately 10 mm at the land surface. A zone of radial compression occurred between the pumping well and the first monitoring station 140 m away from the pumping well. Vertical displacement was measured in decreasing magnitude with increasing distance from the well. Because GPS is not as precise a tool in the vertical direction as it is in the horizontal, the vertical signal of displacement is not as accurate.
Numerical simulations using the BIOT and IBS codes were performed to reproduce the aquifer test and land deformation. The model included six layers representing three hydrogeologic units: a bottom aquifer (four layers) in which pumping occurred , a top aquifer (one layer) in which the monitoring well was screened, and a semi-confining bed (one layer) between the two aquifers that represented an equivalent thickness of interbeds and clays layers. The Biot code was used to simulate radial and vertical movements in an axisymmetrical simulation, while the IBS code was used to simulate only vertical displacement but also provided for the simulation of elastic and inelastic storage and compression.
The vertical distribution of radial displacement was simulated using the BIOT code. At the onset of pumping, the greatest radial displacement occurred in the bottom aquifer in which pumping occurred. At a distance of 2,000 m from the well, the radial displacement was uniform over all depths indicating that the differences in hydraulic diffusivity are not as important a factor at distance from the well.
The change in porosity that occurred as a result of horizontal strain was greatest in the bottom aquifer. Using the strain calculated directly from the GPS measurements at the land surface, vertical strain comprised almost 99% of the volume strain at the land surface. However, when the strain was simulated over the entire aquifer system, the radial and hoop strain contributed more than vertical strain in the bottom aquifer at a radius of 100 m from the pumping well at the onset of pumping until the aquifer reached near equilibrium, at which time vertical strain again dominated.Master of Science
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Matos, Artur José Soares. "Melhorias qualitativas na modelagem de levantamentos batimétricos em reservatórios por meio da ferramenta computacional \"CAV-NH\"." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-25102012-104425/.
Abstract:
A água doce é um recurso mineral finito e essencial para sustentar a vida na terra. Para um bom gerenciamento dos recursos hídricos em uma bacia hidrográfica é importante que se conheça a curva Cota-Área-Volume (CAV) dos reservatórios. Concessionárias de energia e empresas públicas se pautam nesta relação em suas tomadas de decisões considerando os usos múltiplos que os reservatórios apresentam atualmente. Devido ao processo de assoreamento que o reservatório apresenta, é necessário que esta relação seja atualizada com certa frequência, tendo como base os levantamentos batimétricos atualizados. Entretanto, quanto maior o espaçamento entre as seções batimétricas maiores são as falhas que a modelagem do terreno apresenta e maiores os erros que as curvas CAV apresentam. Este estudo visa aprimorar os procedimentos realizados para modelagem de dados batimétricos em reservatórios, apresentando o método denominado Inserção de Malha de Pontos (IMP), que gera uma malha de pontos entre as seções levantadas corrigindo os efeitos de borda gerados pelo interpolador TIN. Com o intuito de otimizar e reduzir o tempo de obtenção dos resultados também é apresentada a ferramenta computacional CAV-NH, desenvolvida em linguagem Python, que utiliza a biblioteca do Arcgis 9.3 para realizar a modelagem do terreno e calcular a curva CAV como resultado final. Para a avaliação e validação do método foi realizada uma batimetria detalhada do reservatório do Lobo-SP, com intervalos entre as seções batimétricas de 10 metros, a qual foi comparada com diferentes espaçamentos até o intervalo de 600 metros. O método também foi aplicado aos reservatórios de Bariri e Ibitinga para a verificação de sua eficácia. Para todos os 1830 casos analisados houve uma melhora significativa na precisão, tendo uma redução no erro do volume calculado maior que 50% para o caso do distanciamento de 200 metros entre as seções, para a cota 703 metros. As análises indicam que o método IMP provê uma modelagem mais condizente com o relevo do terreno de fundo, obtendo-se uma maior acurácia e possibilitando a diminuição do trabalho de coleta de dados em campo sem prejudicar o cálculo do volume do reservatório. O CAV-NH foi utilizado em todas as simulações e se mostrou uma ferramenta de fácil utilização, proporcionando uma maior agilidade em todo processo. Conclui-se que o método IMP juntamente com a ferramenta computacional CAV-NH são importantes contribuições para a definição de uma curva Cota-Área-Volume de qualidade, sendo esta de grande importância para sistemas de suporte à decisão e para um bom gerenciamento dos recursos hídricos.Freshwater is a finite mineral resource and essential for sustaining life on earth. For proper water resource management in the watershed, it is important to know the reservoirs Elevation-Area-Volume (EAV) curve. Energy companies and government agencies use this curve for their decision-making, considering the multiple uses of the reservoirs. Due to the reservoir sedimentation process, it is necessary to update this curve frequently, based on the bathymetric surveys. However, a greater space between transects causes failures in the terrain model and also in the EAV curve. This study aims to improve the procedures used for modeling reservoir survey data, introducing the method called Insertion of Mesh Points (IMP), that generates a mesh of points between transects correcting the edge effects caused by TIN interpolation. In order to optimize and reduce work time for obtaining the results, a computational tool CAV-NH, which was developed in Python language, is also presented. It employs the Arcgis 9.3 library to generate the terrain model and obtain the EAV table. For the evaluation and validation of the method, a detailed bathymetry of the Lobo reservoir was carried out, with 10 meter intervals of survey lines, which was compared with different survey lines spacing up to 600 meters. To verify its effectiveness the method was also applied to Bariri and Ibitinga reservoirs. For all 1830 cases analyzed there was a significant accuracy improvement. For the case of 200 meter line spacing and 703 meters elevation, the error of volume obtained was reduced by more than 50%. The analysis showed that the IMP method provides a terrain model more suited, resulting in greater accuracy and allowing the work reduction of reservoir survey without affecting the volume calculation. The CAV-NH was used in all simulations and proved an easy tool to use, providing greater agility in the whole process. It is concluded that the IMP method and the computational tool CAV-NH are important contributions to achieve a quality relationship of elevation-area-volume.
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Silva, César Helou Teodoro da. "Estudo do ruído de rodagem estrutural através da análise dos caminhos de transferência de energia - TPA." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-22122011-223637/.
Abstract:
Os ruídos, vibrações e asperezas de rodagem veicular (do acrônimo em inglês Road NVH), presentes de 20 Hz até 1000 Hz aproximadamente, originam-se das vibrações e propagações acústicas dos pneus ao interagir com as superfícies. Nestas fontes de ruído, ambas as vias de contribuições estruturais e aéreas, são relevantes para o refinamento veicular. Constantes são os esforços para estudar o veículo como um conjunto de caminhos de transferência entre a dinâmica dos pneus até o conforto dos passageiros. Sendo assim, o tratamento dos mecanismos que geram e propagam o ruído e vibração à cabine está avançando, graças aos testes e análises sistemáticas, fundamentadas na teoria de Análises dos Caminhos de Transferências de energia (TPA do inglês transfer path analysis). O objetivo deste trabalho é apresentar um estudo de um caso de Road NVH utilizando o TPA em veículo protótipo. Neste tema, é investigado o nível de ruído de rodagem em torno de 180 Hz, semelhante ao efeito de roncar (rumble, na expressão em inglês). Este ruído permanece presente no protótipo, em diversos tipos de pista e velocidades, porém em apenas um modelo de pneu (batizado de modelo \"A\"), entre os diversos testados. Das avaliações subjetivas prévias, defini-se que o foco das investigações são as contribuições estruturais da suspensão dianteira. Usando o TPA para demonstrar os caminhos críticos na formação do rumble, aplicou-se o método da matriz inversa para o calculo das forcas, considerando os seguintes pontos: buchas do braço de controle do A-Arm e de ligação da carroceria com a parte superior da suspensão dianteira (fig. 4.6 - tipo Mc Pherson). Foram obtidas experimentalmente as vibrações dos lados ativos e passivos destes pontos, nas condições de rolagem e as funções de resposta vibracionais e acústica do ponto, no laboratório. Após a correlação do ruído interno calculado com o medido, concluiu-se que o rumble deste caso foi gerado pela baixa eficiência de isolação das vibrações radiais nas buchas anteriores e pela força lateral do pneu \"A\". Por fim, propostas de bucha e pneu são apresentadas em termos das novas forças e respostas acústicas transmitidas, para minimizar o rumble.The road noise, vibration and harshness (Road NVH) present from 20 Hz to 1000 Hz approximately, begins from the tires vibration and acoustic propagation and their interactions with the road surfaces. In these noise sources, both structural-borne and air-borne noise contributions are relevant to vehicle refinement. The constant efforts to study the vehicle as a set of transfer paths from tires dynamic behavior to passenger comfort to the final passenger comfort perception. Thus the treatment of generation and propagation mechanisms, have being forward thanks to the systematic tests and proceedings based on the transfer path analysis theory (TPA). The purpose of this work is to present a case study of Road NVH, using TPA in prototype vehicle. On this theme, it is investigated a higher noise level around 180 Hz, on the rumble narrow band. This noise remains in the prototype during several types of tracks and speeds conditions, whenever only a tire model, named as sample A, is used, despites all tires tested. From the previous subjective evaluation, the focus of the investigation is defined to be structure-borne of the front suspension. Using TPA to demonstrate the critical paths to rumble, it was applied the matrix inversion method to force calculation, considering the follow points: A-Arm type lower control arm bushings and top mounts of front suspension (picture 4.6 - Mc Pherson type). The vibration in the active and passive side of these points during test conditions and the FRFs driving points and body sensitivity for a target microphone were obtained experimentally. After correlation between internal road noise calculated and the measured, it was concluded the Rumble of this case had been formed by low radial vibration isolation of the front bushings and due lateral forces of tire A. At last, the bushing and tire proposals are presented in terms of new transmitted forces and acoustical responses, to minimize the rumble.
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Ivanič, Michal. "Návrh testovacího stavu diferenciálu pro zástavbu v bezdozvukové komoře." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-432503.
Abstract:
The diploma thesis describes the design of a test stand for experimental determination of vibroacoustic parameters of a part of the powertrain system. Thesis contains a research part, describing the problems of the drive system, vibroacoustics, measuring devices and also the division and the description of test stands. At the same time, the reasons for choosing a closed loop test stand are explained. Thesis also includes the results of analytical calculations and numerical results of FEM methods performed using ANSYS software, as well as drawing documentation of individual parts.
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Vilca, Edson Emilio Garambel. "Síntese de um intermediário indólico-piperidínico, visando a síntese total do ácido lisérgico." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/75/75133/tde-09022015-165711/.
Abstract:
Os alcalóides ergolínicos são uma categoria de compostos que possuem um esqueleto tetracíclico [6,5,6,6] derivados da ergolina. Do ponto de vista farmacológico, estes compostos são uma classe de produtos naturais importantes, já que exibem uma grande variedade de atividade biológica. Estas moléculas têm sido alvos sintéticos devido ao seu complexo esqueleto tetracíclico e as propriedades supracitadas, o que resultou no desenvolvimento de sínteses totais ao longo do tempo. O ácido lisérgico é o representante notável da família dos alcaloides ergolínicos, uma vez que desde o ano de 1956 até 2013 foram desenvolvidas treze sínteses totais do mesmo. Por isso, o nosso grupo de pesquisa propõe uma rota sintética para a construção de um intermediário indólico-piperidinico, que será usado para realizar a síntese total estereosseletiva do ácido lisérgico em um trabalho de pesquisa futuro. A estratégia para a síntese do intermediário baseia-se na reação de Horner-Wadsworth-Emmons (HWE) e na reação de inserção N-H intramolecular a partir de um aminoaldeído derivado do L-triptofano. A rota sintética inicia-se a partir da elaboração do reagente de olefinação de HWE em três etapas: reação de Michaelis Becker, hidrogenólise catalítica e formação do diazofosfonato. A construção do aminoaldeído requer cinco etapas: esterificação, proteção com Boc, desproteção seletiva, redução do éster e oxidação de Swern. O reagente de olefinação e o aminoaldeído reagem através da reação HWE, fornecendo a diazocetona α, β -insaturada com configuração preferencial Z (Z:E=10:1). Finalmente a olefina Z reage mediante a reação de inserção N-H intramolecular, para fornecer o intermediário indólico-piperidínico. Adicionalmente, desenvolveu-se outra rota para construir o intermediário mencionado através da construção de um derivado de 4-nitroindol, porém esta não foi reprodutível. A síntese do intermediário indólico-piperidínico foi feita em sete etapas, partindo do L-triptofano com rendimento global de 14.9 %.The ergot alkaloids are a class of compounds which have the tetracyclic skeleton [6,5,6,6] found in the ergoline molecule. These compounds are an important class of natural products that have wide biological activities. They have also been important synthetic targets due to their challenging tetracyclic skeleton as well as due to the previously mentioned biological properties. Lysergic acid is the main representative of the family of ergot alkaloids. Since 1956, thirteen total syntheses have been developed for this alkaloid. Considering the importance of lysergic acid and of the ergot alkaloids, our research group decided to propose a synthetic route to construct an advanced indole-piperidinic intermediate, which may be used to perform the total synthesis of lysergic acid and derivatives in a future work. The strategy to the synthesis of this advanced intermediate is based on the Horner-Wadsworth-Emmons reaction (HWE) and the intramolecular N-H insertion reaction, starting from a L-tryptophan aminoaldehyde derivative. The synthetic route started with the elaboration of the HWE olefination reagent in three steps: Michaelis Becker reaction, hydrogenolysis and diazophosphonate formation. In continuation, the construction of the aminoaldehyde required five steps: esterification, Boc protection, selective deprotection, ester reduction and Swern oxidation. The olefination reagent and the aminoaldehyde reacted by the HWE reaction furnishing an α, β -unsaturated diazoketone with Z configuration (Z:E = 10:1). Finally the Z isomer reacted by means of an intramolecular N-H insertion reaction to provide the indole-piperidine intermediate. Additionally, we developed another route to construct a 4-nitro-indole intermediate, but this was not reproducible. The synthesis of the indole-piperidine intermediate was carried out in seven steps starting from L-tryptophan, with an overall yield of 14.9%.
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Miotto, Ronei. "Estudo de primeiros princípios de semicondutores III-N e adsorção de 'NH IND 3' e 'NF IND. 3' na superfície de Si." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/43/43133/tde-11012001-192040/.
Abstract:
Utilizando a Teoria do Funcional da Densidade e uma Dinâmica Molecular Quântica que envolve o formalismo de pseudopotenciais de primeiros princípios, fizemos cálculos de energia total, estrutura atômica e eletrônica, e ligação química para o cristal perfeito e a superfície do GaAs e das fases cúbicas do BN, AlN, GaN e InN para determinar o papel da aproximação do gradiente generalizado (GGA) no funcional da energia de troca e correlação. Nossos cálculos mostram que o efeito combinado da correção não linear de caroço e da aproximação GGA é responsável por mudanças significativas nos parâmetros estruturais e na estrutura eletrônica das superfícies polares (001), independentemente da ionicidade do elemento estudado, mas não é decisivo para o cristal perfeito e para a superfície não polar (110). Nossos cálculos para a superfície (110) sugerem que o ângulo de rotação da ligação entre o cátion e o ânion que compõe a superfície é muito menor para os nitretos: em torno de '15 GRAUS' comparado com '30 GRAUS'^='2 GRAUS' observado para outros semicondutores III-V. Neste trabalho propomos um modelo com uma relação linear entre o deslocamento vertical do cátion e do ânion da camada superficial e o comprimento de ligação superficial após a relaxação para todos os semicondutores III-V e II-VI. Além disso, observamos que a superfície (110) de todos os compostos III-V e II-V apresentam estruturas eletrônicas muito similares. Também procedemos estudos detalhados da estrutura atômica e eletrônica das reconstruções (1x1), (2x2), c(2x2) e (1x4) terminadas em gálio da fase cúbica do GaN crescido na direção (001). Observamos que apenas a reconstrução (1x4) apresenta caráter semicondutor e que é a mais favorável do ponto de vista energético, com um ganho de 0,29 eV por célula unitária (1x1) quando comparada a reconstrução (1x1). A incorporação do nitrogênio em estruturas cristalinas foi inicialmente testada considerando a dissociação e posterior adsorção das moléculas 'NH IND. 3' e 'NF IND. 3' sobre a reconstrução (2x1) da superfície de silício crescida na direção (001). Nossos cálculos apontam que quando da adsorção, em ambos os casos, os dímeros de Si são simétricos e seu comprimento de ligação é maior do que o observado para a superfície livre. As estruturas eletrônicas obtidas indicam que a adsorção das moléculas de amônia e de trifluoreto de nitrogênio resultam na passivação da superfície de silício.
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Rosa, Silas Luis Sartori Paschoal da Silva. "Estudo da correlação entre os resultados de testes e a aplicação dos conceitos de Gerenciamento de Projetos para omodelamento matemático da durabilidade de um componente automotivo." Instituto de Matemática, 2012. http://repositorio.ufba.br/ri/handle/ri/21349.
Abstract:
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Existem inúmeras ferramentas para auxliar os engenheiros de CAE no desenvolvimento de novos produtos, como por exemplo: CAD (computer aided design), CAE (computer aided engineering), CAM (computer aided manufacturing), QFD e TRIZ, entre outros. Este trabalho apresenta uma aplicação dos conceitos de gerenciamento de projetos para a simulação computacional da durabilidade virtual afim de auxiliar os profissionais da área de CAE no design de componentes automotivos. Neste trabalho, foram aplicados os conceitos do dFmea para aprimorar os resultados obtidos na utilização dos conceitos do QFD e da TRIZ. Em adicional, serão aplicados os conceitos do diagrama P, matriz morfológica e matriz de Pugh. O método apresentado para aperfeiçoar a durabilidade utiliza a simulação computacional para correlacionar os resultados obtidos com a aplicação das ferramentas de gerenciamento de projetos. Para realizar a simulação computacional foi utilizado o software MSC_Nastran 2004 R2, Sol 103 (modos normais). Apresenta tambem as diferenças entre dois tipos de modelamentos matemáticos utilizando os pontos de fixação da peça avaliada de maneiras diferentes. Por fim, apresenta os resultados dos testes de laboratório, com o objetivo de comprovar a abordagem teórica apresentada nesta dissertação.
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Ferrero, Poschetto Lorenza. "Comparison of the resistance of feline calicivirus (FCV) and norovirus (NV) against four disinfectants containing organic acids (Venno Vet 1 super), glutaraldehyde (Venno FF super), a halogen compound (sodium hypochlorite ; bleach), and a peroxide (Oxstrong FG) in suspension and carrier tests, as determined by cell culture assay and RT-PCR /." Giessen : VVB Laufersweiler, 2008. http://d-nb.info/989809110/04.
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Bartoněk, Vratislav. "Omega Sport Olomouc - centrum sportu a zdraví, stavebně technologická příprava stavby." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226983.
Abstract:
The master's thesis is elaborated on the basis of the project of the Sport and Health Center Olomouc. The project consists of two main buildings – the object of NH Hotel and the Sports Center Omega. The hotel also includes a conference center with three conference halls and covered parking. The object of Omega Sports Center is composed of sports halls for squash, badminton and tennis, along with changing rooms, wellness area and operational background of the object itself. The sports center also incorporates outdoor tennis courts and an underground tunnel connecting the Omega center and the NH Hotel. This thesis deals with the civil technological project of the building site and involves mainly the technical report of civil technological project, the study of realization of the main technological stages of the building object, the project of organization of construction, time schedule of aforementioned two main buildings, the technological standard with test and execution plans for the execution of underground construction by the impermeable concrete technology and for execution of variant solution of tennis hall roofing. Further, a comparison of the alternative roofing technology with current used roofing technology is performed, including the drawing documentation of new roofing alternative.
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Amitrano, Davide. "Emission acoustique des roches et endommagement : approches experimentale et numerique, application a la sismicite miniere." Grenoble 1, 1999. http://www.theses.fr/1999GRE10002.
Abstract:
Lors de la sollicitation mecanique des roches, la propagation de fissures provoque l'emission d'une onde acoustique (ea) ainsi qu'une modification des proprietes elastiques du materiau. L'ea est donc un moyen direct pour etudier l'evolution de l'endommagement, depuis le stade diffus jusqu'a celui ou il se localise pour former une discontinuite macroscopique. L'ea est egalement consideree comme un modele a petite echelle de la sismicite induite par les travaux souterrains ou de celle de la croute terrestre. En effet, on observe a ces differentes echelles des distributions en loi puissance (exposant b) qui indiquent une invariance d'echelle. La premiere partie de ce travail est consacree a une etude experimentale de l'ea du granite du sidobre en compression triaxiale. Nous montrons que l'ea est liee a un comportement macroscopique non lineaire et peut etre utilisee comme un estimateur de l'endommagement. L'augmentation de la pression de confinement rend le comportement mecanique plus ductile et fait diminuer l'exposant b. Nous proposons, dans la deuxieme partie, un modele numerique base sur l'endommagement elastique et sur la methode des elements finis. Ce modele permet de simuler les principales observations concernant l'ea et le comportement des roches. En particulier, il permet de simuler un comportement macroscopique allant du fragile avec un endommagement localise au ductile avec un endommagement diffus avec un seul parametre de controle : l'angle de frottement interne. En utilisant des valeurs experimentales de ce parametre, nous parvenons a simuler les transitions fragile-ductile et localise-diffus observees lorsque la pression de confinement augmente. La troisieme partie concerne l'etude de la sismicite induite dans une mine. Le caractere critique de la distribution de la taille des seismes est propose comme un critere de surveillance du risque sismique. La relation entre l'exposant b et la dimension de correlation spatiale des sources sismiques est etudiee.
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Ribeiro, Manuel António. "NVL: uma linguagem de coordenação para redes de véiculos autónomos." Master's thesis, 2014. http://hdl.handle.net/10451/15869.
Abstract:
Tese de mestrado, Engenharia Informática (Engenharia de Software), Universidade de Lisboa, Faculdade de Ciências, 2014O uso de veículos autónomos não tripulados tem-se vindo a massificar recentemente com as mais diversas aplicações. Em particular, muitos cenários podem beneficiar do uso cooperativo de vários veículos em rede, tornando-se então imprescindível a concepcão de sistemas de software apropriados para o efeito. Frequentemente, a condução de operações em cenários multi-veículo ainda resulta de especificações separadas por veículo, que se compõem depois em tempo de execução de forma relativamente ad-hoc, e requerendo um elevado grau de intervenção humana. Em contraste, propomos a escrita de “programas de rede” que possam definir o comportamento global de múltiplos veículos autónomos, com uma semântica bem fundada e um alto grau de automação. Tendo esta proposta geral em mente, foi desenhada e implementada uma linguagem de coordenação para redes de veículos autónomos, a Networked Vehicles’ Language (NVL). Um programa NVL define a coordenação global de veículos selecionados numa rede e a associação de tarefas a veículos ou grupos de veículos, com expressividade para padrões de temporização, sequência, concorrência, e escolha no fluxo de um programa. Em suporte ao corpo principal de um programa, as tarefas são definidas por controladores multiveículo cujo código pode ser sintetizado automaticamente. O desenvolvimento da NVL decorreu em colaboração com o Laboratório de Sistemas e Tecnologia Subaquática (LSTS) da Faculdade de Engenharia da Universidade do Porto, que há mais de uma década desenvolve de raiz veículos autónomos e um toolchain de software associado. A NVL foi desenhada e implementada por forma a ser compatível com o toolchain do LSTS, e foi avaliada em simulação e ainda experiencias de campo com veículos reais do LSTS.
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Vlachová, Nela. "Projevy japonské zbožnosti a nábožnského smýšlení v textech jókjoku." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-310892.
Abstract:
Japanese Devoutness and Religious Care Embodied in the Yokyoku Texts This Master's thesis deals with the religious issues within the texts of the medieval Noh plays, which are well known as the yokyoku. The thesis begins with an introduction with the main religious notions and the way of thinking in the period of japanese Middle Ages, in the time when the most of the Noh playwrights wrote their plays. Further more, the thesis provides the very first translation of the Noh play called Kinuta into the Czech language, so that it could be possible to thoroughly analyze its text in terms of religious issues' presence. The thesis also submits the similar analysis of other four plays, which deal almost the same topics. That research allows to arrange the list of religious links and references appearing in those texts. The list proves the presence of the religious issues within the particular artistic genre. Another part of the thesis provides a comparison of yokyoku texts with so called setsuwa legends of the Shasekishu collection, which represents a deeply moralizing work from the Middle Ages, just to identify exactly the degree of the religious devoutness within yokyoku texts. The thesis draws on information and knowledge upon the field of the japanese history, the japanese religious, as well as the...
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Elster, Judith. "Die Bedeutung von Aquaporin1- und Aquaporin4-Konzentrationen im Liquor cerebrospinalis für Patienten mit Normaldruckhydrozephalus und Pseudotumor cerebri." Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B2A5-4.
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"Estudo de primeiros princípios de semicondutores III-N e adsorção de 'NH IND 3' e 'NF IND. 3' na superfície de Si." Tese, Biblioteca Digital de Teses e Dissertações da USP, 1999. http://www.teses.usp.br/teses/disponiveis/43/43133/tde-11012001-192040/.