This thesis purposes and develops inductively coupled LC (inductive-capacitive) pH sensors based on pH-sensitive electrode pair. The LC resonator circuit is based on a varactor and measures the low frequency potential difference. For wireless pH monitoring, the resonator circuit is integrated with a pH-sensitive electrode pair. This sensor demonstrates a linear response over 2 to 12 pH dynamic range, 0.1 pH accuracy and long-term stability. Accurate measurement of pH using electrode-based sensors is affected by temperature variation. A technique of simultaneously measuring two parameters, pH and temperature, with a single RLC resonator based sensor is presented. An algorithm is developed, which applies both pH and temperature measurement to incorporate temperature compensation in pH measurement. For in-fluid applications, an encapsulation method is applied to the LC resonator based sensor to reduce the influence of medium permittivity and conductivity on the sensor measurement. Non-invasive way to obtain reliable pH information from bacterial culture bioprocesses is demonstrated with the fluid embeddable sensor. The pH sensor is remodeled to an acidic and basic volatile sensor by embedding the electrodes in a hydrogel host electrolyte. Tests demonstrate that the volatile sensor has a detection limit of 1.5 ppm and 2 ppm for ammonia and acetic acid vapor, respectively. Application of the volatile sensor to fish spoilage monitoring shows that the sensor is capable of detecting the product rejection level with good sensitivity in real-time. It is important to develop low cost wireless passive pH sensor technologies for embedded applications such as bioprocess and food spoilage monitoring. The electrode-based passive LC sensor approach employed in this thesis overcomes drawbacks of some of the early developed passive pH sensors and can lead to an inexpensive implementation using printed electronics technology.

The remarkable evolution of wireless networks into the next generation to provide ubiquitous and seamless broadband applications has recently triggered the emergence of Wireless Mesh Networks (WMNs). The WMNs comprise stationary Wireless Mesh Routers (WMRs) forming Wireless Backbone Mesh Networks (WBMNs) and mobile Wireless Mesh Clients (WMCs) forming the WMN access. While WMCs are limited in function and radio resources, the WMRs are expected to support heavy duty applications : that is, WMRs have gateway and bridge functions to integrate WMNs with other networks such as the Internet, cellular, IEEE 802.11, IEEE 802.15, IEEE 802.16, sensor networks, et cetera. Consequently, WMRs are constructed from fast switching radios or multiple radio devices operating on multiple frequency channels. WMRs are expected to be self-organized, self-configured and constitute a reliable and robust WBMN which needs to sustain high traffic volumes and long "online" time. However, meeting such stringent service expectations requires the development of decentralized dynamic transmission power control (DTPC) approaches. This thesis addresses the DTPC problem for both single and multiple channel WBMNs. For single channel networks, the problem is formulated as the minimization of both the link-centric and network-centric convex cost function. In order to solve this issue, multiple access transmission aware (MATA) models and algorithms are proposed. For multi-radio multi-channel (MRMC) WBMNs, the network is modelled as sets of unified channel graphs (UCGs), each consisting of interconnected active network users communicating on the same frequency channel. For each UCG set, the minimization of stochastic quadratic cost functions are developed subject to the dynamic Link State Information (LSI) equations from all UCGs. An energy-efficient multi-radio unification protocol (PMMUP) is then suggested at the Link-Layer (LL). Predictive estimation algorithms based on this protocol are proposed to solve such objective functions. To address transmission energy and packet instabilities, and interference across multiple channels, singularly-perturbed weakly-coupled (SPWC) control problems are formulated. In order to solve the SPWC transmission power control problem, a generalized higher-order recursive algorithm (HORA) that obtains the Riccati Stabilizing Solutions to the control problem is developed. The performance behaviours of the proposed models and algorithms are evaluated both analytically and through computer simulations. Several simulations are performed on a large number of randomly generated topologies. Simulation and analytical results confirm the efficacy of the proposed algorithms compared to the most recently studied techniques

An importantmatter in the field of building physics is the questioning of how wellbuildings sustain ageing, and how their overall efficiency evolves over their lifetime.Many causes for degradation are carried by moisture transfer through these porousmaterials. Indeed, infiltratedwatermay transport chemicals, altermechanical properties,and cause freeze thaw damage or mould development. It may also affect thermalproperties and energetic efficiency, as well as the health and comfort of the occupants.The understanding of how moisture transfer properties evolve during the lifespan ofbuildingmaterials is however far fromcomplete. The pore structure of amaterial itselfmay change over time, or be altered by cracks and defects caused bymechanical loadingand aggravated bymoisture-induced degradation. All sizes of fracturesmay have astrong impact on heat and moisture flow in the building envelope, and their influenceis to be accounted for in any long-termperformance assessment, not only of buildingand building components,but of any built structure in general. A considerable amountof work has already been performed in order to allow predicting the hygrothermal behaviourof buildings over longer periods of time. However, an accurate prediction of allranges of damage in a building component, from microscopic to macroscopic cracks,supposes an extensive knowledge of all damage-inducing, time-varying boundary conditionsof the problem during the simulation time. This also implies high computationalcosts, as well as important needs formaterial characterisation.As a complement to these predictive methods, a new approach was undertaken,combining experimental characterisation of crack patterns and numerical simulationsof coupled heat and moisture transfer. First, a preliminary study was conducted, consistingof measurements of the water vapour permeability of diffusely damaged constructionmaterials.This allowed identifying the experimental and numerical requirementsof the remainder of the work, which aimed at providing measurements of fracturenetwork geometries for their explicitmodelling in heat andmoisture transfer simulations.Digital image correlation and acoustic emission monitoring were then performedduring the degradation of cementitiousmaterials, in order to obtain quantitativedata on crack pattern geometries, and to assess the possibilities for damagemonitoringat the building scale. The optical technique, along with an appropriate imageprocessing procedure, was found suitable for providing precisemeasurements of fracturenetworks. Amethodwas also proposed for the interpretation of acoustic emissionrecordings in terms of damage quantification, localisation and identification.Then, a newmodel for coupled heat andmoisturemodelling in cracked porousmediawas developed, that allows including such measurements of fracture patterns intoa finite element mesh, and simulating flow accordingly. This model was validated onthe basis of experimentalmeasurements: digital image correlationwas performed duringthe fracturing of concrete samples, in which moisture uptake was then monitoredusing X-ray radiography. A good accordance was found between experimental and numericalresults in terms of 2-dimensional moisture concentration distributions. The validated code was then used for the simulation of test cases, in order to assess the hygrothermalperformance of damagedmulti-layered building components subjected toreal climatic conditions. The consequences of fractures on themoisture accumulationin walls, on the amplitude of sorption/desorption cycles and on the thermal performance,were observed.

This thesis presents a systematic numerical modeling framework to simulate the stress-deformation and coupled stress-deformation-flow processes by performing uniaxial and biaxial compressive tests on fractured rock models with considering the effects of different loading conditions, different loading directions (anisotropy), and coupled hydro-mechanical processes for evaluating strength and deformability behavior of fractured rocks. By using code UDEC of discrete element method (DEM), a series of numerical experiments were conducted on discrete fracture network models (DFN) at an established representative elementary volume (REV), based on realistic geometrical and mechanical data of fracture systems from field mapping at Sellafield, UK. The results were used to estimate the equivalent Young’s modulus and Poisson’s ratio and to fit the Mohr-Coulomb and Hoek-Brown failure criteria, represented by equivalent material properties defining these two criteria. The results demonstrate that strength and deformation parameters of fractured rocks are dependent on confining pressures, loading directions, water pressure, and mechanical and hydraulic boundary conditions. Fractured rocks behave nonlinearly, represented by their elasto-plastic behavior with a strain hardening trend. Fluid flow analysis in fractured rocks under hydro-mechanical loading conditions show an important impact of water pressure on the strength and deformability parameters of fractured rocks, due to the effective stress phenomenon, but the values of stress and strength reduction may or may not equal to the magnitude of water pressure, due to the influence of fracture system complexity. Stochastic analysis indicates that the strength and deformation properties of fractured rocks have ranges of values instead of fixed values, hence such analyses should be considered especially in cases where there is significant scatter in the rock and fracture parameters. These scientific achievements can improve our understanding of fractured rocks’ hydro-mechanical behavior and are useful for the design of large-scale in-situ experiments with large volumes of fractured rocks, considering coupled stress-deformation-flow processes in engineering practice. / <p>QC 20141111</p>

Cette thèse s'articule autour de développements méthodologiques sur l'évaluation théorique des énergies quantiques et relativistes d'état électroniquement excité d'atome ou de molécule. La méthode basée sur la fonction d'onde "Coupled Cluster" (CC) est à l'heure actuelle, une des méthodes les plus précise pour calculer ces états pour les systèmes à N-corps. L'implémentation présentée est basée sur un Hamiltonien relativiste à N-corps: Dirac-Coulomb à 4 composantes et une fonction d'onde "Coupled Cluster" au rang d'excitation arbitraire. Les états excités sont évalués via la théorie de la réponse linéaire, en diagonalisant la matrice Jacobienne Coupled Cluster. L'accent des travaux se porte sur l'évaluation de ses éléments en seconde quantification via un nouvel algorithme basé sur les commutateurs, et sur son adaptation au formalisme relativiste de Dirac à 4 composantes. Enfin, des applications du code à des molécules diatomiques non triviales seront présentées.

Salinity and turbidity are two important seawater properties for the physical oceanography. The study of physical oceanography requires a compact high-resolution in-situ salino-turbidi-meter. The main objective of this work is to propose, design and implement an optical solution to simultaneously measure the seawater salinity and turbidity. Our first study is carried out to design a high-resolution refractometer based on a laser beam deviation measurement by a Position Sensitive Device (PSD). The refractive index measurements obtained by the voltage value delivered by PSD have been evaluated to quantify the performances of the sensor. According to the obtained results, it is clear that this PSD-based refractometer is attractive for innovative applications in metrology. However, PSD lacks the capability to retrieve the power distribution information of laser beam, which is related to the turbidity measurements. On the contrary, Charge-Coupled Device (CCD) gives much more information of laser beam than PSD. In the second part of the thesis, a performance comparison between PSD and CCD combined with a centroid algorithm are discussed with special attention paid to the CCD-based refractometer. According to the operating principle of CCD-based system, five factors of CCD-based system: image window size, number of processed images, threshold, binning and saturation are evaluated to optimize the CCD-based refractometer. By applying the optimized parameters, the performance of CCD-based refractometer is better than PSD-based refractometer in measuring the refractive index. Furthermore, by applying different post-processing algorithms, CCD-based system possesses the capability of measuring the power distribution sensitive quantities. To show this advantage of CCD-based system, the attenuation measurement method is used to measure turbidity without modifying the refractometer configuration. The turbidity measurement and salinity measurements influence each other in a refractometer. To overcome these influences, a CCD combined with a new location algorithm is used to measure both the refractive index and the attenuation. Several simulations and experiments are carried out to evaluate this new method. According to the results, the way to improve the resolution is discussed as well. Comparing to the nephelometer specified by the NTU standard, our method has been proved as a valid method to measure turbidity. By studying the performances of CCD-based refracto-turbidi-meter, 3 new prototypes are proposed to improve the salinity and turbidity measurement performance at the end of this thesis.

The objective of this thesis is to develop a novel methodology of fractional stochastic dynamics to study stochastic stability of viscoelastic systems under stochastic loadings. Numerous structures in civil engineering are driven by dynamic forces, such as seismic and wind loads, which can be described satisfactorily only by using probabilistic models, such as white noise processes, real noise processes, or bounded noise processes. Viscoelastic materials exhibit time-dependent stress relaxation and creep; it has been shown that fractional calculus provide a unique and powerful mathematical tool to model such a hereditary property. Investigation of stochastic stability of viscoelastic systems with fractional calculus frequently leads to a parametrized family of fractional stochastic differential equations of motion. Parametric excitation may cause parametric resonance or instability, which is more dangerous than ordinary resonance as it is characterized by exponential growth of the response amplitudes even in the presence of damping. The Lyapunov exponents and moment Lyapunov exponents provide not only the information about stability or instability of stochastic systems, but also how rapidly the response grows or diminishes with time. Lyapunov exponents characterizes sample stability or instability. However, this sample stability cannot assure the moment stability. Hence, to obtain a complete picture of the dynamic stability, it is important to study both the top Lyapunov exponent and the moment Lyapunov exponent. Unfortunately, it is very difficult to obtain the accurate values of theses two exponents. One has to resort to numerical and approximate approaches. The main contributions of this thesis are: (1) A new numerical simulation method is proposed to determine moment Lyapunov exponents of fractional stochastic systems, in which three steps are involved: discretization of fractional derivatives, numerical solution of the fractional equation, and an algorithm for calculating Lyapunov exponents from small data sets. (2) Higher-order stochastic averaging method is developed and applied to investigate stochastic stability of fractional viscoelastic single-degree-of-freedom structures under white noise, real noise, or bounded noise excitation. (3) For two-degree-of-freedom coupled non-gyroscopic and gyroscopic viscoelastic systems under random excitation, the Stratonovich equations of motion are set up, and then decoupled into four-dimensional Ito stochastic differential equations, by making use of the method of stochastic averaging for the non-viscoelastic terms and the method of Larionov for viscoelastic terms. An elegant scheme for formulating the eigenvalue problems is presented by using Khasminskii and Wedig’s mathematical transformations from the decoupled Ito equations. Moment Lyapunov exponents are approximately determined by solving the eigenvalue problems through Fourier series expansion. Stability boundaries, critical excitations, and stability index are obtained. The effects of various parameters on the stochastic stability of the system are discussed. Parametric resonances are studied in detail. Approximate analytical results are confirmed by numerical simulations.

Biogene Amine sind kleine organische Verbindungen, die sowohl bei Wirbeltieren als auch bei Wirbellosen als Neurotransmitter, Neuromodulatoren und/oder Neurohormone wirken können. Sie bilden eine bedeutende Gruppe von Botenstoffen und entfalten ihre Wirkungen über die Bindung an eine bestimmte Klasse von Rezeptorproteinen, die als G-Protein-gekoppelte Rezeptoren bezeichnet werden. Bei Insekten gehören zur Substanzklasse der biogenen Amine die Botenstoffe Dopamin, Tyramin, Octopamin, Serotonin und Histamin. Neben vielen anderen Wirkung ist z.B. gezeigt worden, daß einige dieser biogenen Amine bei der Honigbiene (Apis mellifera) die Geschmacksempfindlichkeit für Zuckerwasser-Reize modulieren können. Ich habe verschiedene Aspekte der aminergen Signaltransduktion an den „Modellorganismen“ Honigbiene und Amerikanische Großschabe (Periplaneta americana) untersucht. Aus der Honigbiene, einem „Modellorganismus“ für das Studium von Lern- und Gedächtnisvorgängen, wurden zwei Dopamin-Rezeptoren, ein Tyramin-Rezeptor, ein Octopamin-Rezeptor und ein Serotonin-Rezeptor charakterisiert. Die Rezeptoren wurden in kultivierten Säugerzellen exprimiert, um ihre pharmakologischen und funktionellen Eigenschaften (Kopplung an intrazelluläre Botenstoffwege) zu analysieren. Weiterhin wurde mit Hilfe verschiedener Techniken (RT-PCR, Northern-Blotting, in situ-Hybridisierung) untersucht, wo und wann während der Entwicklung die entsprechenden Rezeptor-mRNAs im Gehirn der Honigbiene exprimiert werden. Als Modellobjekt zur Untersuchung der zellulären Wirkungen biogener Amine wurden die Speicheldrüsen der Amerikanischen Großschabe genutzt. An isolierten Speicheldrüsen läßt sich sowohl mit Dopamin als auch mit Serotonin Speichelproduktion auslösen, wobei Speichelarten unterschiedlicher Zusammensetzung gebildet werden. Dopamin induziert die Bildung eines völlig proteinfreien, wäßrigen Speichels. Serotonin bewirkt die Sekretion eines proteinhaltigen Speichels. Die Serotonin-induzierte Proteinsekretion wird durch eine Erhöhung der Konzentration des intrazellulären Botenstoffs cAMP vermittelt. Es wurden die pharmakologischen Eigenschaften der Dopamin-Rezeptoren der Schaben-Speicheldrüsen untersucht sowie mit der molekularen Charakterisierung putativer aminerger Rezeptoren der Schabe begonnen. Weiterhin habe ich das ebony-Gen der Schabe charakterisiert. Dieses Gen kodiert für ein Enzym, das wahrscheinlich bei der Schabe (wie bei anderen Insekten) an der Inaktivierung biogener Amine beteiligt ist und im Gehirn und in den Speicheldrüsen der Schabe exprimiert wird. / Biogenic amines are small organic compounds that act as neurotransmitters, neuromodulators and/or neurohormones in vertebrates and in invertebrates. They form an important group of messenger substances and mediate their diverse effects by binding to membrane receptors that primarily belong to the large gene-family of G protein-coupled receptors. In insects, the group of biogenic amine messengers consists of five members: dopamine, tyramine, octopamine, serotonin, and histamine. Besides many other effects, some of these biogenic amines were shown, for example, to modulate gustatory sensitivity to sucrose stimuli in the honeybee (Apis mellifera). I have investigated various aspects of the aminergic signal transduction in the “model organisms” honeybee and American cockroach (Periplaneta americana). So far, I have characterized two dopamine receptors, a tyramine receptor, an octopamine receptor and a serotonin receptor of the honeybee, which is well-known for its learning and memory capacities. The receptors where expressed in cultivated mammalian cells in order to analyze their pharmacological and functional (i.e., second messenger coupling) properties. The spatiotemporal expression patterns of the respective receptor mRNA were investigated in the honeybee brain by using different techniques (RT PCR, Northern blotting, in situ-hybridization). The salivary glands of the American cockroach were used as a model object in order to investigate the cellular effects of biogenic amines. Both dopamine and serotonin trigger salivary secretion in isolated salivary glands. The quality of the secreted saliva is, however, different. Stimulation of the glands by serotonin results in the production of a protein-rich saliva, whereas stimulation by dopamine results in saliva that is protein-free. Serotonin-induced protein secretion is mediated by an increase in the intracellular concentration of cAMP. The pharmacological properties of dopamine receptors associated with cockroach salivary glands were investigated and the molecular characterization of putative aminergic receptors of the cockroach was initiated. Furthermore, I have characterized the ebony gene of the cockroach. This gene encodes an enzyme that is probably involved in the inactivation of biogenic amines in the cockroach (as in other insects). The ebony gene is expressed in the brain and in the salivary glands of the cockroach.

Opioid Receptors (ORs) are involved in the pathophysiology of several neuropsychiatric conditions yet remain an untapped therapeutic resource. Although only mu-, delta-, and kappa-OR types have been cloned, additional subtypes result from complexes generated by direct receptor-receptor interactions. Mu- and delta-ORs form a heteromeric receptor complex with unique pharmacological and signalling properties distinct from those of mu- and delta-OR homomers. In these studies, we sought to characterize the ligand binding pocket and agonist-induced internalization profile of the mu-delta heteromer, to investigate mu-delta heteromer-specific signalling in brain, and to interrogate the contribution of this receptor complex to opioid-mediated behavioural effects. In competition radioligand binding studies, delta-agonists displaced high affinity mu-agonist binding from the mu-delta heteromer but not the muOR homomer, suggestive of delta-agonists occupying or allosterically modulating the muOR ligand binding pocket within the heteromer. Delta-agonists induced internalization of the mu-delta heteromer in a dose-dependent, pertussis toxin resistant, and muOR- and deltaOR-dependent manner from the cell surface via the clathrin and dynamin endocytic machinery. Agonist-induced internalization of the mu-delta heteromer persisted following chronic morphine treatment conditions which desensitized the muOR homomer. Using Galpha-specific GTPgammaS binding assays, we demonstrated that mu-delta heteromer signalling previously characterized in cell lines was present in the striatum and hippocampus, and did not desensitize following prolonged morphine treatment conditions which desensitized muOR homomer-mediated signalling. Since delta-agonists which also target the mu-delta heteromer possess antidepressant-like and anxiolytic-like properties, we investigated the role of this receptor complex in mood regulation. We devised a strategy to selectively analyze the effects of the mu-delta heteromer by dissociating it using a specific interfering peptide aimed at a sequence implicated in mu-delta heteromerization. The interfering peptide abolished the unique pharmacological and trafficking properties of delta-agonists at the mu-delta heteromer and dissociated this receptor complex in vitro. Intra-accumbens administration of the interfering peptide disrupted the mu-delta interaction in vivo and allowed for isolation of the mu-delta heteromer contribution to the mood-regulatory effects of a delta-agonist with activity at the heteromer. Activation of the mu-delta heteromer in the nucleus accumbens produced antidepressant-like and anxiolytic-like actions in animal models of depression and anxiety.

Opioid Receptors (ORs) are involved in the pathophysiology of several neuropsychiatric conditions yet remain an untapped therapeutic resource. Although only mu-, delta-, and kappa-OR types have been cloned, additional subtypes result from complexes generated by direct receptor-receptor interactions. Mu- and delta-ORs form a heteromeric receptor complex with unique pharmacological and signalling properties distinct from those of mu- and delta-OR homomers. In these studies, we sought to characterize the ligand binding pocket and agonist-induced internalization profile of the mu-delta heteromer, to investigate mu-delta heteromer-specific signalling in brain, and to interrogate the contribution of this receptor complex to opioid-mediated behavioural effects. In competition radioligand binding studies, delta-agonists displaced high affinity mu-agonist binding from the mu-delta heteromer but not the muOR homomer, suggestive of delta-agonists occupying or allosterically modulating the muOR ligand binding pocket within the heteromer. Delta-agonists induced internalization of the mu-delta heteromer in a dose-dependent, pertussis toxin resistant, and muOR- and deltaOR-dependent manner from the cell surface via the clathrin and dynamin endocytic machinery. Agonist-induced internalization of the mu-delta heteromer persisted following chronic morphine treatment conditions which desensitized the muOR homomer. Using Galpha-specific GTPgammaS binding assays, we demonstrated that mu-delta heteromer signalling previously characterized in cell lines was present in the striatum and hippocampus, and did not desensitize following prolonged morphine treatment conditions which desensitized muOR homomer-mediated signalling. Since delta-agonists which also target the mu-delta heteromer possess antidepressant-like and anxiolytic-like properties, we investigated the role of this receptor complex in mood regulation. We devised a strategy to selectively analyze the effects of the mu-delta heteromer by dissociating it using a specific interfering peptide aimed at a sequence implicated in mu-delta heteromerization. The interfering peptide abolished the unique pharmacological and trafficking properties of delta-agonists at the mu-delta heteromer and dissociated this receptor complex in vitro. Intra-accumbens administration of the interfering peptide disrupted the mu-delta interaction in vivo and allowed for isolation of the mu-delta heteromer contribution to the mood-regulatory effects of a delta-agonist with activity at the heteromer. Activation of the mu-delta heteromer in the nucleus accumbens produced antidepressant-like and anxiolytic-like actions in animal models of depression and anxiety.