[pt] Dispositivos opto-eletrônicos são elementos semicondutores que convertem radiações eletromagnéticas em corrente elétrica, e vice e versa. Os fotodetectores são dispositivos desse tipo, os quais possuem grande relevância na atualidade, devido a suas diversas aplicações. As pesquisas atuais se concentram no estudo de fotodetectores à base de poços quânticos para operar no infravermelho médio (2-20 m), mais especificamente em super-redes. No presente trabalho foi desenvolvido um fotodetector de duas cores baseado em super-redes assimétricas. O fotodetector construído possui uma rede com duas sessões. A primeira sessão tem cinco poços quânticos e cinco barreiras com 2 nm e 3.5 nm de espessura, respectivamente. A segunda sessão possui cinco poços quânticos e cinco barreiras de 2 nm e 7 nm de espessura, respectivamente. Entre as seções existe um poço quântico de 2.5 nm. O material que forma os poços quânticos é de InGaAs e o material das barreiras é de AlInAs. Esse dispositivo foi capaz de operar como um fotodetector de duas cores operando no modo fotovoltaico detectando radiações de 309 meV e 415 meV. O dispositivo foi capaz de operar em altas temperaturas. A temperatura máxima de operação foi de 245 K. Além disso, ao se aplicar tensões no dispositivo, é possível selecionar a radiação a ser detectada pelo fotodetector. Sendo elas 309 meV ou 415 meV. / [en] Opto-electronic devices are semiconductor elements that convert electromagnetic radiation in electric current. Photodetectors are devices of this type, which are the main relevant ones today due to their diverse applications. Current research focuses on the study of photodetectors based on quantum wells for operation in the medium infrared (2-20 m), more specifically with superlattices. In the present work a photodetector of two cores based on asymmetric superlattice was developed. The built-in photodetector had a superlattice with two sessions The first session had five quantum wells and five barriers with 2 nm and 3.5 nm of thickness, respectively. The second session had five quantum wells and five barriers of 2 nm and 7 nm thick, respectively. Between the sessions there is a 2.5 nm quantum well. The material that formed the quantum wells was InGaAs and the material of the barriers was AlInAs. This device was able to operate as a dual color photodetector operating in the photovoltaic mode detecting radiation of 309 meV and 415 meV. The device was able to operate at high temperatures. The maximum operating temperature was 245 K. In addition, when applying voltages to the device, it is possible to select the detection energy of the photodetector :309 meV or 415 meV.

No description available.

Mitochondria are the power plant of most non-green eukaryotic cells. In order to understand mitochondrial functions and their regulation, knowledge of the spatiotemporal organization of their proteins is important. Mitochondrial membrane proteins can diffuse within membranes. They are involved in diverse functions e.g. protein import, cell respiration, metabolism, metabolite transport, fusion, fission or formation of the mitochondrial architecture. Furthermore, mitochondria compose of different subcompartments with different tasks. Especially, the inner mitochondrial membrane (IM), where the oxidative phosphorylation (OXPHOS) takes places, has a complex architecture with cristae extending into the matrix. The present work revealed the restricted localization of some mitochondrial proteins to specific membrane sections and linked it to their function or bioenergetic circumstances in the living cell. 
Single particle tracking (SPT) techniques like tracking and localization microscopy (TALM) allow to localize proteins with a precision below 20 nm. Additionally, tracking single proteins provides information about their mobility, dynamic and their spatiotemporal organization. TALM uses proteins, which were genetically tagged either with the HaloTag® (HaloTag) or the fSnapTag® (fSnapTag). These tags can be orthogonally and posttranslationally stained with specific and self-marking dyes. If the dyes are conjugated to the respective substrate of the tag. Single molecule labeling of mitochondrial proteins was performed substoichiometrically using membrane permeable rhodamine dyes, either tetramethylrhodamine (TMR) or silicon rhodamine (SiR). TALM allowed to localize proteins in different mitochondrial subcompartments. The gained trajectories and trajectory maps of mitochondrial proteins revealed their spatiotemporal organization. In the case of IM proteins like F1FO ATP synthase (Complex V - CV) a restricted diffusion in the CM, which is part of the continuous IM, was determined. The unimpeded diffusion of mitochondrial proteins in the outer mitochondrial membrane (OM) was compared with the mobility of IM proteins. The diffusion of mitochondrial IM proteins was restricted by the IM architecture and their diffusion coefficients were lower. Furthermore, significant differences of different mitochondrial IM proteins were compared, showing different localizations in the IM often coupled to their function, accompanied by different spatiotemporal organization and diffusion coefficients. Furthermore, a distinction was made between diffusion of proteins in the inner boundary membrane (IBM) and proteins that preferentially diffuse in the cristae membrane (CM). Evaluating trajectory maps, the different subcompartments in the IM were revealed by trajectories and the trajectory directionality, allowing the identification of mitochondrial proteins, which mark these subcompartments.
The morphology of mitochondria / mitochondrial networks and their bioenergetic parameters are linked to the metabolic states of the cell. In this work, the connection of the spatiotemporal protein organization of CV and the IM architecture was uncovered on the micro- and nanoscopic level and linked to the metabolic state of the cell. It was determined that the spatiotemporal organization of the CV was altered, when CV was inhibited. In addition, the bioenergetic influence of cells on the spatiotemporal behavior of CV and the reorganization of the IM architecture was investigated by TALM and compared with results of electron microscopy images. It was shown that starvation of cells led to a loss of cristae and thus to an increased mobility and spatiotemporal reorganization of CV. Taken together, the results presented in this work showed that a correctly functioning and active CV helps to maintain the IM architecture and both, the spatiotemporal organization of CV and the IM architecture were coupled to the metabolic state.. 
In order to investigate putative protein-protein interactions by colocalization and co-locomotion studies on single molecule level, dual color SPT is needed. Therefore, posttranslational and substoichimetric labeling as performed in TALM was tested for its potential of protein-protein interaction studies of mitochondrial membrane proteins. Here, a genetically double tagged translocase of the outer membrane subunit-20 (Tom20) (Tom20:HaloTag:fSnapTag) acted as a positive control. It turned out that substoichimetric, posttranslational labeling of mitochondrial proteins was not suitable for protein-protein interaction studies on mitochondrial proteins, because it was restricted by the low labeling degrees needed for TALM. However, dual-color TALM still allowed to study effects of proteins influencing the IM architecture and to study their influence on the spatiotemporal organization of CV. The co-transfection of Mic10, as the central protein of the mitochondrial inner membrane organizing system / mitochondrial contact site complex / mitochondrial organizing structure (MINOS / MICOS / MitOS (MINOS/MICOS)), altered the regular and aligned organization of the cristae. This was measured by a changed spatiotemporal organization of the CV, such as the loss of the perpendicular oriented of CV subunit-γ (CV-SUγ) cristae trajectories. In contrast to this, co-transfection of CV subunit-e (CV-SUe), important for dimerization of CV, increased the number of cristae trajectories. 
Mitochondria are three-dimensional (3D) cell organelles. Consequently, subcompartments like the IBM and CM are a 3D space in which CV is localized and diffuses. Thus, the diffusion of mitochondrial proteins is underestimated by two-dimensional SPT e.g. lateral confined diffusion can result from mitochondrial proteins diffusing along the z-axis of the microscope. In order to reveal the 3D spatiotemporal organization of CV, the potential of TALM to be extended to a 3D-SPT technique was investigated. Therto a cylindrical lens was installed in the emission path of a total internal reflection fluorescence (TIRF) microscope. This leads to an astigmatically distorted point spread function (PSF) of the fluorescent single molecule signals. This distortion allowed the reconstruction of single molecule localizations of CV to a superresolved image of the IM, in living cells. In addition, 3D-TALM enabled to display the 3D architecture of the IM by 3D trajectories of CV. 3D-TALM was able to detect whether CV diffuses in the IBM or in the CM, and extended the information about its mobility in the CM that it takes place in a disc-like manner. In this way it could be shown that CV is mobile within the cristae in all directions. Finally, 3D-TALM revealed an altered IM architecture caused by the metabolic state of the cell. As performed in two-dimensional TALM, the cells were kept under starving conditions. Here the now tubular IM architecture was revealed by 3D-TALM. The reversed metabolic state under improved respiratory conditions unexpectedly led to a more diverse IM architecture. These ultrastructural changes were also revealed by electron microscopy. Consequently, 3D-TALM enabled the study of IM architecture by tracking CV under different metabolic conditions, allowing an ultrastructural analysis of mitochondria in living cells. In addition, 3D TALM provided the spatiotemporal organization of CV under different metabolic conditions, so that the diffusion coefficients of CV could be related to changes in IM architecture caused by the metabolic condition.

Mapping of earth resources, environmental monitoring, and many other systems require high-resolution wide-area imaging. Since images often have to be captured at night or in inclement weather conditions, a capability is provided by Synthetic Aperture Radar (SAR). SAR systems exploit radar signal's long-range propagation and utilize digital electronics to process complex information, all of which enables high-resolution imagery. This gives SAR systems advantages over optical imaging systems, since, unlike optical imaging, SAR is effective at any time of day and in any weather conditions. Moreover, advanced technology called Interferometric Synthetic Aperture Radar (InSAR), has the potential to apply phase information from SAR images and to measure ground surface deformation. However, given the current state of technology, the quality of InSAR data can be distorted by several factors, such as image co-registration, interferogram generation, phase unwrapping, and geocoding. Image co-registration aligns two or more images so that the same pixel in each image corresponds to the same point of the target scene. Super-Resolution (SR), on the other hand, is the process of generating high-resolution (HR) images from a low-resolution (LR) one. SR influences the co-registration quality and therefore could potentially be used to enhance later stages of SAR image processing. Our research resulted in two major contributions towards the enhancement of SAR processing. The first one is a new learning-based SR model that can be applied with SAR, and similar applications. A second major contribution is utilizing the devised model for improving SAR co-registration and InSAR interferogram generation, together with methods for evaluating the quality of the resulting images. In the case of phase unwrapping, the process of recovering unambiguous phase values from a two-dimensional array of phase values known only modulo $2\pi$ rad, our research produced a third major contribution. This third major contribution is the finding that quantum annealers can resolve problems associated with phase unwrapping. Even though other potential solutions to this problem do currently exist - based on network programming for example - network programming techniques do not scale well to larger images. We were able to formulate the phase unwrapping problem as a quadratic unconstrained binary optimization (QUBO) problem, which can be solved using a quantum annealer. Since quantum annealers are limited in the number of qubits they can process, currently available quantum annealers do not have the capacity to process large SAR images. To resolve this limitation, we developed a novel method of recursively partitioning the image, then recursively unwrapping each partition, until the whole image becomes unwrapped. We tested our new approach with various software-based QUBO solvers and various images, both synthetic and real. We also experimented with a D-Wave Systems quantum annealer, the first and only commercial supplier of quantum annealers, and we developed an embedding method to map the problem to the D-Wave 2000Q_6, which improved the result images significantly. With our method, we were able to achieve high-quality solutions, comparable to state-of-the-art phase-unwrapping solvers. / Graduate

No description available.

The production industry is getting more and more automated and that implies higher energy consumption. With the increasing awareness of the earth limited resources and the increasing energy prices, energy conservation grows in relevance, both due to cost reduction and environmental benefits. One way to conserve energy is to optimize the energy usage within the business and reduce the losses. Regenerative braking is already in use today for this purpose in vehicles. The aim of this thesis is to investigate how regenerative braking can be fitted into the production industry and what adaptations need to be made. This thesis is based on an earlier study that has set up a mathematical model for energy regeneration in mechatronic systems and the goal of this thesis is to build a test rig and verify the correctness of these models. One suggested improvement to the automotive systems are the introduction of super capacitors as a secondary energy source because they can charge more rapidly compared to batteries which is required during the expected fast accelerations. In the performed tests an efficiency improvement of 10 % was shown. The earlier study however suggests an efficiency rate of 60% but those models do not include frictional nor electrical losses. The results are complemented by a discussion were a number of changes to the design is proposed. A different motor control system would significantly enhance the rig and a result more like the expected can be achieved. / Det ökade antalet elektromekaniska maskiner i industriella tillämpningar medför en ökad energianvändning. Då våra begränsade resurser mer och mer belyses i media och med stigande energipriser ökar intresset hos företagen för att minska sin energianvändning, dels för att reducera sina kostnader och dels för att minska den miljöbelastning slutprodukten medför. Ett sätt att göra detta är att minska energiförlusterna inom sin produktion. Regenerativ bromsning är en teknik som används i fordon idag och kan användas för detta syfte. Detta arbete ska undersöka hur sådan teknik kan användas i tillverkningsindustrin och vilka förändringar som måste göras. Ett tidigare arbete har satt upp teoretiska modeller för detta och det här arbetet syftar till att bygga en tesrigg för att praktiskt undersöka modellernas korrekthet. En förbättring mot det system som används i dagens bilar är att införa superkondensatorer som parallell energikälla då dessa är snabbare på att lagra energi än ett batteri och därför passar bättre för de snabba accelerationer och retardationer som förekommer i industriprocesser. De genomförda testerna påverkades negativt av vissa begränsningar i hårdvaran men resultatet visar ändå att regenereringen kan återföra 10 % av energin till kondensatorerna, det motsvarar däremot inte den mängden som de tidigare uppsatta modellerna förutspådde. Orsakerna är olika förluster i systemet som inte modellerna tar hänsyn till. De viktigaste förlustfaktorerna beror på friktion och styrningen av elektroniken. Med en annan typ av motorstyrning kan förlusterna minskas och ett resultat mer likt det förväntade uppnås.

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This thesis proposes a method for determining the optimal antenna element radiation characteristics which maximize diversity gain given a specific power angular spectrum of the propagation environment. The method numerically constructs the eigenfunctions of the covariance operator for the scenario subject to constraints on the power radiated by each antenna as well as the level of supergain allowed in the solution. The optimal antenna characteristics are produced in terms of radiating current distributions along with their resulting radiation patterns. The results reveal that the optimal antennas can provide significantly more diversity gain than that provided by a simple practical design. Computational examples illustrate the effectiveness of adding additional elements to the optimal array and the relationship between aperture size or the description of the impinging field and the array performance. A synthesis procedure is proposed which uses genetic algorithm optimization to optimally place a reduced number of dipoles. The results from this procedure demonstrate that using the framework in conjunction with optimization strategies can lead to practical designs which perform well relative to the upper performance bound. Finally a novel array architecture is proposed where subsets of antennas are combined together into super-elements which are then combined in the same manner as the optimal array. The simplifications that result from the genetically optimized small array or the super-element array provide a design options which are feasible in many communication applications.

<p>High-throughput phenotyping has emerged as a powerful approach to expedite crop breeding programs. Modern remote sensing systems, including manned aircraft, unmanned aerial vehicles (UAVs), and terrestrial platforms equipped with multiple sensors, such as RGB cameras, multispectral, hyperspectral, and infrared thermal sensors, as well as light detection and ranging (LiDAR) scanners are now widely used technologies in advancing high throughput phenotyping. These systems can collect high spatial, spectral, and temporal resolution data on various phenotypic traits, such as plant height, canopy cover, and leaf area. Enhancing the capability of utilizing such remote sensing data for automated phenotyping is crucial in advancing crop breeding. This dissertation focuses on developing deep learning and transfer learning methodologies for crop phenotyping using multi-modality remote sensing and environmental data. The techniques address two main areas: multi-temporal/across-field biomass prediction and multi-scale remote sensing data fusion.</p> <p><br></p> <p>Biomass is a plant characteristic that strongly correlates with biofuel production, but is also influenced by genetic and environmental factors. Previous studies have shown that deep learning-based models are effective in predicting end-of-season biomass for a single year and field. This dissertation includes development of transfer learning methodologies for multiyear,</p> <p>across-field biomass prediction. Feature importance analysis was performed to identify and remove redundant features. The proposed model can incorporate high-dimensional genetic marker data, along with other features representing phenotypic information, environmental conditions, or management practices. It can also predict end-of-season biomass using mid-season remote sensing and environmental data to provide early rankings. The framework was evaluated using experimental trials conducted from 2017 to 2021 at the Agronomy Center for Research and Education (ACRE) at Purdue University. The proposed transfer learning techniques effectively selected the most informative training samples in the target domain, resulting in significant improvements in end-of-season yield prediction and ranking. Furthermore, the importance of input remote sensing features was assessed at different growth stages.</p> <p><br></p> <p>Remote sensing technology enables multi-scale, multi-temporal data acquisition. However, to fully exploit the potential of the acquired data, data fusion techniques that leverage the strengths of different sensors and platforms are necessary. In this dissertation, a generative adversarial network (GAN) based multiscale RGB-guided model and domain adaptation framework were developed to enhance the spatial resolution of multispectral images. The model was trained on limited high spatial resolution images from a wheel-based platform and then applied to low spatial resolution images acquired by UAV and airborne platforms.</p> <p>The strategy was tested in two distinct scenarios, sorghum plant breeding, and urban areas, to evaluate its effectiveness.</p>

In the thesis the author attempts to focus on what value Career theories (such as turning points, planned happenstance, SCCT and PEC) may have for guidance counselors, and their clients. The author describes a number of theories, then put them to use on a number of interviews where clients describe their present career situation to guidance counselor students. The author reaches the conclusion that career theories have an important value for guidance counselors and their clients; Career theories play an important role in helping to understand the client´s behavior and history of choices. Career theories can also be used by the guidance counselor to help the client in future choices.