Den här uppsatsen är uppbygd så att den följer min konsnärliga och personliga utveckling under tiden på konstfack. Den första delen innehåller en teoridel som sedan följs upp av beskrivningar av mina arbeten. Parallellt med detta löper en berättande text om mitt liv och min relation till kläder som jag haft innan jag började på Konstfack. / Textil formgivning / Master 2009 Textile in the Expanded Field

Vertical structure of the low frequency horizontal currents at the northern edge of the Loop Current during eddy shedding events is observed using concurrent hydrographic, moored, and satellite altimetry data from 2005. Dynamic modes are calculated at three deep (~3000 m), full water-column moorings in the eastern Gulf of Mexico. Time-series of the barotropic and first two baroclinic modes are found using a least squares minimization that fits theoretically derived modes to observed moored velocity data. EOF analyses show that the majority of observed variance is explained by a surface-trapped mode that is highly coherent with the temporal amplitudes of the first baroclinic mode, and a lower, but significant percentage of variance is captured in bottom-intensified modes. Amplitudes of the second empirical mode indicate that currents are more coherent in the ocean interior approaching the Loop Current, as more variance is explained by this mode at the southernmost mooring near the Loop Current. A dynamic mode decomposition of the horizontal currents reveals that the barotropic and first baroclinic modes exhibit low frequency variability and eddy time scales of 10 – 40 days. Second baroclinic mode amplitudes show higher frequency variability and shorter time scales. A model utility test for the least squares fit of modeled to observed velocity shows that the second baroclinic mode is useful to the statistical model during 50 – 85 % of the mooring deployment, and is particularly necessary to the model when cyclonic features are present in the study area. The importance of the second baroclinic mode to the model increases significantly closer to the Loop Current. High-speed currents associated with the Loop Current and anticyclones stimulate a strong first baroclinic response, but the second baroclinic mode amplitudes are found to be similar in magnitude to the first baroclinic mode amplitudes at times. This happens episodically and could be an indication of higher order dynamics related to frontal eddies or Loop Current eddy shedding.

This thesis is study about the capability of guided waves in the inspection of cracks in pipelines, and studying about the guided waves of mode conversion phenomenon caused by cracks. The generally used inspection methods in industry are all localized area inspection. It will cost expensively and spend lots of human resource and time consuming, if we want to inspect the whole area in pipelines in factory. Thus, guided waves are used to improve these shortcomings of traditional inspection methods. Guided Waves can propagate fast and long range along the pipelines without decay. With the ability that guided waves can incident at a single location then inspect the whole region of pipelines under efficiently propagating distance. In this thesis, with using laboratory equipment, 3 Toneburst Cycles, 400¡B500¡B600 kHz, and L(0,1)¡BL(0,2) incident mode set up for crack detective sensitivity experiment. By calculating the group velocity of the signals of crack, it is known that there are three separated modes L(0,1)¡BL(0,2) and F(1,2) from reflected waves by cracks. These modes are exactly mode converted by cracks. The results show that in the same crack circumferential length or crack depth, the longer length or the deeper depth cause the higher reflection coefficient. It means they are more sensitive on the inspection of cracks. Also the reflection coefficient increases with the raising cross section area loss of cracks. In two dimensional fast Fourier transform experiment (2-D FFT), with 3 Toneburst Cycles, 400¡B500¡B600 kHz, L(0,1)¡BL(0,2) incident mode, and 0.5 cm interval set up to gather 40-point signals for proceeding the experiment. It can separate signals with different group velocity which are mixing together in time domain. From results, there are three different modes L(0,1)¡BL(0,2) and F(1,2) mode separated at three-dimensional picture. Finally, using the guided waves inspection system with 3 toneburst, 90 kHz and T(0,1) incident mode set up to proceed the experiment as before. In inspecting crack sensitive experiment, the use of this system has the similar result with the use of laboratory equipment. It proves that the excellent capability of guided waves in inspection of cracks in pipelines. While in mode identification, this system can identify there is only T(0,1) and F(1,2) mode with the same group velocity exist. Then the same result is verified by 2-D FFT experiment. It shows that this system generate or receive the specific mode in detection cracks by phase construction or phase destruction of phase interference.

Based on Lyapunov stability theorem, a design methodology of nth order adaptive integral variable structure derivative estimator (AIVSDE) is proposed in this thesis. The proposed derivative estimator not only is an improved version of the existing AIVSDE, but also can be used to estimate the nth differentiation of a smooth signal which has continuous and bounded derivatives up to n+1. A low pass filter is cascaded with AIVSDE so that the effects of noise can be alleviated by adjusting the designing parameters of filter and AIVSDE. The adaptive algorithm is incorporated in the control scheme for removing the a priori knowledge of the upper bound of the observed signal. The stability of the proposed derivative estimator is guaranteed, and the comparison of upper bound of derivative estimation error between recently proposed nonlinear adaptive variable structure derivative estimator (NAVSDE) and AIVSDE is also demonstrated. An example is given for showing the applicability of the proposed AIVSDE.

Present day optical integrated circuits contain many continuously bending waveguides making it important to study EM field profiles of bending waveguides. The mostly widely used numerical method for analyzing bending waveguides is the beam propagation method (BPM). Although it can calculate very fast, BPM results are not accurate enough in many wide-angle applications due to BPM¡¦s intrinsic paraxial approximation. Recently, full-wave based finite-difference time-domain technique has become quite popular and has been used to study many optical devices. Unfortunately it can not be used to study smoothly bending waveguides due to huge computational resource requirements needed for these large optical devices. In the absence of reflection in a bending waveguide, other one way, wide-angle methods can be applied. In this thesis we propose two such methods to analyze different kinds of bending waveguides. We use full eigen-mode expansion technique (FEMET) when reflection is negligible. In cases where reflection is strong, we propose a cylindrical couple transverse-mode integral-equation (C-CTMIE) to do the job. Both FEMET and CTMIE methods are built on complete sets of circular layered modes of the underlying structure. These modes are not easy to solve because the standard cylindrical mode solver requires extensive references to Bessel functions of complex arguments and orders. Here in this thesis, we proposed to expand cylindrical layered modes from planar layered modes of an equivalent structure. In essence, we renormalize the existing planar layered waveguide modes and turn them into desired circular layered modes. We show that using a matrix eigenvector formulation, this relatively simple technique is not only quite fast but also produces very accurate results. Finally using these circular modes various S-bend waveguides are analyzed. We also present a design to minimize the radiation loss of a circular waveguide using whisper gallery modes.

Recently, the evolutions of wireless communication systems are growing rapidly to satisfy the personal communication requirements. Compact, small size, low cost, easy fabrication, and multi-function are the major developing trends among these modern wireless communication devices. In this research, high quality Al2O3 ceramic materials are used as a substrate to fabricate modifiable dual-mode bandpass filters with the advantages of light weight, small size, and high performance. Dual mode cavity and dielectric resonator filters are the mainstay of satellite communications. In this research, a class generation of planar dual mode filters are introduced which significantly offers the advantages of small size, light weight, and low cost. The proposed bandpass filters are first simulated on Al2O3 (er=9.4) substrate for microwave frequency, and the proposed structures consist one square-typed patch, one circle-typed patch, or one meander-typed patch. Each pattern is connected with two 50£[ microstrip line, one for input and another for output. Two 50£[ microstrip lines are connected to the central of the patch with two notches, and the patch will act as the elliptic-function bandpass filters. Before the fabrication of a bandpass filter, IE3D microwave simulation software is used to simulate the designed filters. With a metal mask, the filter patterns are fabricated on the Al2O3 substrate by using evaporation method. It is found that as the length of notches increase, the three of structures band-pass filters reveal better filtering effect, i.e., the smaller insertion loss (S21), and larger return loss (S11), and the perturbation in the patch facilitates coupling between two orthogonal modes within the resonator, i.e., the perturbation size can modify bandwidth and resonator frequency. After the measurement of the fabricated filters, it is found that the measured results will match the simulated results.

This thesis presents the development of a refractometric sensor based on quantum dot-embedded polystyrene microspheres. The technique uses optical resonances within a microsphere, known as Whispering-Gallery Modes (WGMs), which produce narrow spectral peaks. The basic theory of WGMs is reviewed and specifically discussed for biosensing application. The spectral shifts of WGM peaks are sensitive to changes in the local refractive index. In the experiments, two-photon excited luminescence from the quantum dots couples into several WGMs within the microresonator. By optimizing the detection area, the spectral visibility of the WGMs is improved. The spectral shifts are measured as the surrounding index of refraction changes. The experimental sensitivity is about five times greater than that predicted by Mie theory. The sensor element is based on commercially available dielectric microspheres with a diameter about 10 μm. Thus, the technique is more economic and suitable for sensing applications, compared to microspheres of 100 μm in size which can only be made in the laboratory.

Universiẗat, Diss.--Münster, 2007. / Literaturverz. S. IX - XXI.

In the United States, permanent hearing loss affects approximately 3 newborns in 1,000 making it the most common birth defect. Current widespread use of universal newborn hearing screening has resulted in an average age of identification of hearing loss of 2-3 months. As the population of children who are identified early in life and fitted with cochlear implants (CI) grows, speech-language pathologists (SLPs) are likely encounter clients from this population. However, the majority of SLPs are not educated as to the various modes of communication that can be used with children with CI as they learn spoken language. The focus of this review is to provide SLPs with an evidence-based resource to guide their decision-making regarding appropriate communication mode for children with CI. / text

No description available.