Trial and error and the use of highly time-consuming methods are often necessary for investigation and characterization of nonlinear systems. However, for the rather common case where a nonlinear system has linear relations between many of its degrees of freedom there are opportunities for more efficient approaches. The aim of this thesis is to develop and validate new efficient simulation and experimental methods for characterization of mechanical systems with localized nonlinearities. The purpose is to contribute to the development of analysis tools for such systems that are useful in early phases of the product innovation process for predicting product properties and functionality. Fundamental research is combined with industrial case studies related to metal cutting. Theoretical modeling, computer simulations and experimental testing are utilized in a coordinated approach to iteratively evaluate and improve the methods. The nonlinearities are modeled as external forces acting on the underlying linear system. In this way, much of the linear theories behind forced response simulations can be utilized. The linear parts of the system are described using digital filters and modal superposition, and the response of the system is recursively solved for together with the artificial external forces. The result is an efficient simulation method, which in conjunction with experimental tests, is used to validate the proposed characterization methods. A major part of the thesis addresses a frequency domain characterization method based on broad-band excitation. This method uses the measured responses to create artificial nonlinear inputs to the parameter estimation model. Conventional multiple-input/multiple-output techniques are then used to separate the linear system from the nonlinear parameters. A specific result is a generalization of this frequency domain method, which allows for characterization of continuous systems with an arbitrary number of localized zero-memory nonlinearities in a structured way. The efficiency and robustness of this method is demonstrated by both simulations and experimental tests. A time domain simulation and characterization method intended for use on systems with hysteresis damping is also developed and its efficiency is demonstrated by the case of a dry-friction damper. Furthermore, a method for improved harmonic excitation of nonlinear systems using numerically optimized input signals is developed. Inverse filtering is utilized to remove unwanted dynamic effects in cutting force measurements, which increases the frequency range of the force dynamometer and significantly improves the experimental results compared to traditional methods. The new methods form a basis for efficient analysis and increased understanding of mechanical systems with localized nonlinearities, which in turn provides possibilities for more efficient product development as well as for continued research on analysis methods for nonlinear mechanical structures.

The geotechnical conditions of the soil can fluctuate greatly across the wind farm. This is an issue since geotechnical modelling is the base of the structural design of an offshore wind farm, and the efficient installation of the wind turbines depends on its accuracy. This paper deals with the characterization of the seabed, predicting the soil properties over the total affected area by a wind farm, with the challenge to reduce the required data samples in the site investigation under the number of installed wind turbines, to reduce its cost. It is compared the prediction outcome from two different interpolation methods, kriging and radial basis function, assessing their accuracy by the Mean-Squared Error and the Goodness-of-Prediction Estimate, as well as with a visual examination of their mapping; obtaining higher accuracy for radial basis function and reducing to half the required sample points, from the initial value of installed wind turbines. In a second stage it is studied the soil effect over the foundation, analyzing the results from a FEA, where different geometries of the structure are compared submitted to different load cases to check its limit states. Those results show that the foundation cost can increase four times due to the soil conditions, taking into account only the steel volume, and demonstrating how important is the soil characterization in the foundation design, as it gives the chance to relocate those wind turbines that require more expensive foundations.

<p>The objective of this thesis is to evaluate a generic process for fabrication and characterization of the Superconductive coplanar waveguide (CPW) resonators. Superconductive CPW resonators with various lengths and shapes are designed to investigate their electrical and magnetic properties as well as resonance properties and sensitivities. In the first part of thesis, two different models are introduced in order to estimate the nonlinear kinetic inductance of a superconducting CPW resonator. The first model is based on Bean critical-state model and the second one is based on current dependence of London penetration depth. The existence of a shift in resonant frequency  of Superconductive CPW resonator caused by a non-linear kinetic inductance is also shown experimentally. Simulations were carried out to estimate the nonlinear kinetic inductance due to the self- induced magnetic field penetration.</p><p>The rest of the thesis is concerned with development of very smooth Aluminum (Al) thin films with RMS (Root Mean Square) roughness 1~nm and CAD (Computer Aid Design) of superconductive CPW resonators. Experimental investigation of a generic fabrication technique for superconductive CPW resonator is carried out. Many resonators are fabricated with different design parameters, such as centerline or gap width, film thickness and gap capacitors length. The fabrication process is described in detail. Electron Beam Lithography is used to fabricate Nb and Al CPW resonators which are coupled to outer conductors via gap capacitors. We have fabricated GHz frequency CPW resonators with quality factors, Q up 5X10^5.</p>

This dissertation is a study of error in long haul optical fiber systems and how to coupe with them. First we characterize error events occurring during transmission, then we determine lower bounds on information capacity (achievable information rates) and at the end we propose coding schemes for these systems.Existing approaches for obtaining probability density functions (PDFs) for pulse energy in long-haul optical fiber transmission systems rely on numerical simulations or analytical approximations. Numerical simulations make far tails of the PDFs difficult to obtain, while existing analytic approximations are often inaccurate, as they neglect nonlinear interaction between pulses and noise.Our approach combines the instanton method from statistical mechanics to model far tails of the PDFs, with numerical simulations to refine the middle part of the PDFs. We combine the two methods by using an orthogonal polynomial expansion constructed specifically for this problem. We demonstrate the approach on an example of a specific submarine transmission system.Once the channel is characterized estimating achievable information rates is done by a modification of a method originally proposed by Arnold and Pfitser. We give numerical results for the same optical transmission system (submarine system at transmission rate 40Gb/s).The achievable information rate varies with noise and length of the bit patterns considered (among other parameters). We report achievable numerical rates for systems with different noise levels, propagation distances and length of the bit patterns considered.We also propose two iterative decoding schemes suitable for high-speed long-haul optical transmission. One scheme is a modification of a method, originally proposed in the context of magnetic media, which incorporates the BCJR algorithm (to overcomeintersymbol interference) and Low-Density Parity-Check (LDPC) codes for additional error resilience. This is a ``soft decision scheme" -meaning that the decoding algorithm operates with probabilities(instead of binary values). The second scheme is ``hard decision" -it operates with binary values. This scheme is based on the maximum likelihood sequence detection-Viterbi algorithm and a hard decision"Gallager B" decoding algorithm for LDPC codes.

N2O chemisorption technique for copper dispersion determination was developed and optimized for accurate and reproducible results. With this technique, the bulk oxidation of pre-reduced catalyst can be prevented by N2O decomposition at low temperature (30oC). Only surface copper atoms are oxidized. The amount of freshly oxidized surface coppers is determined from H2-back-titration of fixed oxygen.The impact of temperature and time of exposure during oxidation was studied. Measurements made at higher temperature (60oC) resulted in overestimation of copper dispersion due to oxygen diffusion into the bulk and sub-layers. Much longer exposure time may also have an impact on copper dispersion estimation.For accurate results and good precision, it is recommended to work under mild conditions (isothermal oxidation at 30oC for 45 min.The developed method was successfully applied to fresh and spent catalyst. As expected, the copper dispersion for fresh catalyst was significantly higher than copper dispersion for spent catalyst.

Nowadays the rapid developments of wireless communication technologies there are more and more ways to look into the RF measurements and designs in detail such as Universal Software Radio Peripheral(USRP) from LabVIEW, Advance Design System(ADS),etc.Moreover a lack of measurements what compared with different digital modulation schemes is becoming a problem. In this thesis by building the simulations of communication system in NI-USRP system and measuring the results then compare with the different PSK system in order to give a deeper insight of this new software of USRP from LabVIEW. and in the end analyze bit error rate varus signal to noise ratio from the PSK system. To get the characterizations of NI-USRP system the first step is to build multiple simulations such as FM receiver, PSK wireless communication systems. By performing the FM receiver is to analyze the quality of the receiving and baseband FM signal. And from the simulation of different PSK communications through the analysis of the performance of BPSK,QPSK,OQPSK and compared with bit error rate it could give an insight of characterization of NI-USRP system and in the end the conclusions give in which kind of prototype or simulation that suit the best of NI-USRP system.

Doctor of Philosophy / Department of Physics / Chii-Dong Lin / Isolated attosecond pulse (IAP) is a tool of probing electronic dynamics occurring in atoms, molecules, clusters and solids, since the time scale of electronic motion is on the order of attoseconds. The generation, characterization and applications of IAPs has become one of the fast frontiers of laser experiments. This dissertation focuses on several aspects of attosecond physics. First, we study the driving wavelength scaling of the yield of high-order harmonic generation (HHG) by applying the quantum orbit theory. The unfavorable scaling law especially for the short quantum orbit is of great importance to attoseond pulse generation toward hundreds of eVs or keV photon energy region by mid-infrared (mid-IR) lasers. Second, we investigate the accuracy of the current frequency-resolved optical gating for complete reconstruction of attosecond bursts (FROG-CRAB) and phase retrieval by omega oscillation filtering (PROOF) methods for IAP characterization by simulating the experimental data by theoretical calculation. This calibration is critical but has not been carefully carried out before. We also present an improved method, namely the swPROOF which is more universal and robust than the original PROOF method. Third, we investigate the controversial topic of photoionization time delay. We find the limitation of the FROG-CRAB method which has been used to extract the photoionization time delay between the 2s and 2p channels in neon. The time delay retrieval is sensitive to the attochirp of the XUV pulse, which may lead to discrepancies between experiment and theory. A new fitting method is proposed in order to overcome the limitations of FROG-CRAB. Finally, IAPs are used to probe the dynamic of electron correlation in helium atom by means of attosecond transient absorption spectroscopy. The agreement between the measurement and our analytical model verifies the observation of time-dependent build up of the 2s2p Fano resonance.

L'objectif de cette thèse a été l'optimisation de la synthèse et des performances catalytiques des matériaux lamellaires au W et Mo dans les réactions d'oxydation de plusieurs composés organiques en présence d'H2O2. Le travail réalisé au cours de cette thèse est le développement de nouveaux catalyseurs hétérogènes pour la réaction d'oxydation qui est réalisée sélectivement en systèmes catalytiques homogènes, mais pour un développement durable, la catalyse hétérogène demeure beaucoup plus porteuse d'avenir au niveau industriel. La réaction d'oxydation de composés soufrés a un grand intérêt, en particulier dans l'élimination des composés organiques soufrés (thiophènes, sulfures) contenus dans les carburants et les coupes pétrolières, réalisée dans des conditions douces de température et pression, en présence de l'eau oxygénée. Les objectifs principaux de cette étude ont été les suivants: 1. élaboration des matériaux catalytiques : a) préparation des précurseurs de type hydrotalcites (HDL) à base de Mg-Al-NO3, Mg-Al-terephthalate et Ni-Mg-Al-NO3. b) préparation des matériaux hybrides par intercalation des espèces de Mo et W par deux voies de synthèse : réaction d'échange anionique et synthèse hydrothermale. 2. caractérisation de la structure, la texture et la nature des sites catalytique par différentes techniques : DRX, adsorption d'azote, ATG, spectroscopie Raman et UV-Vis, MEB etc. 3. applications de ces catalyseurs à la réaction d'oxydation des composes soufrés (sulfures, thiophènes, sulfoxydes), epoxydation de cyclooctene et oxydation d'anthracène. Les catalyseurs ont été stables au recyclage et aucun phénomène de leaching n'a été observé. / The objective of this thesis was the optimization of the synthesis and catalytic performances of nanocomposites materials containing W and Mo in the oxidation with H2O2 of a wide range of model organic compounds. The work achieved during this thesis is the development of new heterogeneous catalysts for the oxidation reaction who is carried out selectively in homogeneous catalytic systems, heterogeneous catalysis is still much more promising in future. The oxidation reaction of sulfur compounds has great interest, especially in the removal of organic sulfur compounds (thiophene, sulfide) contained in fuels and petroleum fractions, performed in mild conditions of temperature and pressure in the presence of H2O2. In this study were as follows : 1. elaboration of materials : a) preparation of precursors of type hydrotalcites (HDL) based on Mg-Al-NO3, Mg-Al-Ni-terephthalate and Mg-Al-NO3. b) preparation of hybrid materials by intercalation species of Mo and W by two synthetic routes : reaction of anion-exchange and hydrothermal synthesis. 2. characterization of the structure, texture and nature of catalytic sites by different techniques : XRD, nitrogen adsorption, TGA, Raman spectroscopy and UV-Vis, SEM, etc. 3. application of these catalysts in the reaction of oxidation of sulfur compounds (sulfides, thiophenes, sulfoxides), epoxidation of cyclooctene and oxidation of anthracene. The catalysts were stable under operating conditions.

Cell-to-cell communication is one of the fundamental requisites of making multicellular organisms. G protein-coupled receptors (GPCRs) are one of the most abundant receptor-types within vertebrates. They canonically mediate their signal via hetrotrimeric G proteins, and G protein signaling is regulated by regulators of G protein-signaling (RGS). One of these RGS proteins, RGS4, is preferentially expressed in the central nervous system of humans and has been strongly connected to dopaminergic signaling, along with a number of severe neuronal diseases. rgs4 is not well studied in the model organism Danio rerio, the zebrafish, with only two publications. In this project, a newly constructed transgenic line, tg(rgs4:mCherry), with the fluorophore mCherry regulated by the promoter element of rgs4 was characterized in order to investigate fidelity to endogenous rgs4 expression and the utility of the transgenic line. The mCherry expression is apparent by 48 hours post fertilization, and expression is found mainly in neuronal tissue. Cell bodies are visible only in some labeled areas, while other areas show a more diffuse signal indicative of projections. There is only one transgenically labeled area that also unambiguously expresses rgs4; the pronephric tubule. This line is therefore not particularly well suited for rgs4-specifc studies, but this does not discredit the fidelity of the construct. A transgenic line made with a site-directed technique would most likely confer the fidelity of the promoter to the expression of the fluorophore. A way of increasing the labeling resolution includes exchanging the mCherry fluorophore for one with stronger signal and a lower tendency to aggregate, e.g. eGFP. Increasing the resolution of the characterization, e.g. to the level of sub-nuclei or neuronal types, would serve to enhance the utility of the line. As it is, the tg(rgs4:mCherry) zebrafish line has limited uses, and yet it is not without them.

This thesis on William Faulkner's concept of knowledge beyond reason includes a study of style and characterization and a study of possible sources.