Though the Aerospace industry is moving towards small satellites and smaller sensor technologies, sensors used for close-proximity operations are generally cost (and often size and power) prohibitive for University-class satellites. Given the need for low-cost, low-mass solutions for close-proximity relative navigation sensors, this research analyzed the expected errors due to near-field effects using a coarse sun sensor as part of a 6-degree-of-freedom (6-dof) solution. To characterize these near-field effects, a test bed (Characterization Test Apparatus or CTA) was proposed, its design presented, and the design stage uncertainty analysis of the CTA performed. A candidate coarse sun sensor (NorthStarTM) was chosen for testing, and a mathematical model of the sensor’s functionality was derived. Using a Gaussian Least Squares Differential Correction (GLSDC) algorithm, the model parameters were estimated and a comparison between simulated NorthStarTM measurements and model estimates was performed. Results indicate the CTA is capable of resolving the near-field errors. Additionally, this research found no apparent show stoppers for using coarse sun sensors for 6-dof solutions.

Observing the relative state of two space vehicles has been an active field of research since the earliest attempts at space rendezvous and docking during the 1960's. Several techniques have successfully been employed by several space agencies and the importance of these systems has been repeatedly demonstrated during the on-orbit assembly and continuous re-supply of the International Space Station. More recent efforts are focused on technologies that can enable fully automated navigation and control of space vehicles. Technologies which have previously been investigated or are actively researched include Video Guidance Systems (VGS), Light Detection and Ranging (LIDAR), RADAR, Differential GPS (DGPS) and Visual Navigation Systems. The proposed system leverages the theoretical foundation which has been advanced in the development of VisNav, invented at Texas A & M University, and the miniaturized commercially available Northstar sensor from Evolution Robotics. The dissertation first surveys contemporary technology, followed by an analytical investigation of the coarse sun sensor and errors associated with utilizing it in the near-field. Next, the commercial Northstar sensor is investigated, utilizing fundamentals to generate a theoretical model of its behavior, followed by the development of an experiment for the purpose of investigating and characterizing the sensor's performance. Experimental results are then presented and compared with a numerical simulation of a single-sensor system performance. A case study evaluating a two sensor implementation is presented evaluating the proposed system's performance in a multisensor configuration. The initial theoretical analysis relied on use of the cosine model, which proved inadequate in fully capturing the response of the coarse sun sensor. Fresenel effects were identified as a significant source of unmodeled sensor behavior and subsequently incorporated into the model. Additionally, near-field effects were studied and modeled. The near-field effects of significance include: unequal incidence angle, unequal incidence power, and non-uniform radiated power. It was found that the sensor displayed inherent instabilities in the 0.3 degree range. However, it was also shown that the sensor could be calibrated to this level. Methods for accomplishing calibration of the sensor in the near-field were introduced and feasibility of achieving better than 1 cm and 1 degree relative position and attitude accuracy in close proximity, even on a small satellite platform, was determined.

This thesis describes an assessment of offshore wind farms using a Matlab tool Marine System simulator. This tool helps to analyse the Vessel motion according to different wave heights. From this assessment one can know the correct weather window for offshore operation and other possible techniques to reduce the time delay in operation. This tool is used to simulate a supply vessel motion according to different wave heights. The chosen supply vessel is the default supply vessel in the simulator.

One of the main advantages of the Gantry-Tau machine is a large accessible workspace\footprint ratio compared to many other parallel machines. The Gantry-Tau improves this ratio further by allowing a change of assembly mode without internal link collisions or collisions between the links and the moving TCP platform. In this Thesis some of the features of the Gantry-Tau structure are described and results are presented from the analysis of the kinematic, elastostatic and elastodynamic properties of the PKM. However, the optimal kinematic, elastostatic and elastodynamic design parameters of the machine are still difficult to calculate and this thesis introduces a multi-objective optimisation scheme based on the geometric approach for the workspace area, unreachable area, joint angle limitations and link collisions as well as the functional dependencies of the elements of the static matrix and the Laplace transform to define the first resonance frequency and Cartesian and torsional stiffness. The method to calculate the first resonance frequency assumes that each link and universal joint can be described by a mass-springdamper model and calculates the transfer function from a Cartesian (TCP) force or torque to Cartesian position or orientation. The geometric methods involve the simple geometric shapes (spheres, circles, segments, etc) and vectors. The functional dependencies are based on the properties between the kinematic parameters. These approaches are significantly faster than analytical methods based on the inverse kinematics or the general Finite Elements Method (FEM). The reconfigurable Gantry-Tau kinematic design obtained by multi-objective optimisation gives the following features: • Workspace/footprint ratio more than 3.19. • First resonance frequency greater than 48 Hz. • Lowest Cartesian stiffness in the workspace 5N/μm. • The unreachable space in the middle of the workspace is not detected. • No link collisions. The results show that by careful design of the PKM, a collision free workspace without the unreachable area in the middle can be achieved. High stiffness and high first resonance frequency are important parameters for the the Gantry-Tau when used in industrial applications, such as cutting, milling and drilling of steel or aluminium and pick-and-place operations. These applications require high static and dynamic accuracy in combination with high speed and acceleration. The optimisation parameters are the support frame lengths, actuator positions,endeffector kinematics and the robot’s arm lengths. Because of the fast computational speed of the geometric approaches and computational time saving of the methods based on the functional dependency, they are ideal for inclusion in a design optimisation framework, normally a nonlinear optimisation routine. In this Thesis the evolutionary algorithm based on the complex search method is used to optimise the 3-DOF Gantry-Tau. The existing lab prototype of this machine was assembled and completed at the University of Agder

Abstract Transcription factors (TFs) play an indispensable role in cell biology as they are responsible for regulating gene activity. TFs act by binding to specific DNA sequences in a gene promoter resulting in either activation or repression of transcription of the target gene. TFs interact with target genes through a DNA binding domain which is often highly conserved and can be used to classify TFs into families. Dof (DNA binding with one finger) TFs are classified by the presence of a highly conserved bi-functional Dof domain. Characterisation of various Dof proteins has identified essential regulatory roles in plant-specific processes. This includes roles in carbon metabolism in maize, seed development and germination in Arabidopsis and cereal crops and circadian responses in Arabidopsis and rice. Despite the important role of Dof proteins in plant growth and development, this family has been studied to a limited extent in wheat with only two Dof proteins reported to date. Therefore, the aim of this thesis is to identify and initiate characterisation of the Dof TF family in wheat (Triticum aestivum) and investigate the potential role of members of this family in wheat productivity-associated physiological processes. Thirty-one Dof genes were identified after extensive searching of available Triticum aestivum ESTs and contig assembly. Phylogenetic analysis grouped these 31 genes into four clades. Extensive gene expression profiling of the TaDof family was undertaken and revealed that the majority of TaDof members were constitutively expressed in major vegetative organs with a few displaying a grain-predominant expression pattern. The TaDof family appears to be enriched with light-responsive or drought down-regulated members, suggesting that the role of this family is predominantly in growth-related processes. To further investigate their role in growth-related physiological processes, two Dof genes, TaDof4 and TaDof5, were selected for more detailed characterisation. TaDof5 was identified to be similar to the Cycling Dof Factors from Arabidopsis and the recently identified rice Dof daily fluctuations genes which are involved in the photoperiodic regulation of flowering time. TaDof5 gene expression was diurnally regulated, had strong expression in the stem and head and a peak in expression level at anthesis. Using publicly available Affymetrix data, correlation analysis suggested co-expression of TaDof5 with a number of circadian-regulated genes associated with flowering. Extensive analysis of the DNA-binding specificity of TaDof5 revealed a preferred binding motif of 5’GAAAAAGTGC. The binding of TaDof5 to DNA requires two (A/T)AAAG(T/C) core motifs in adjacent positions. The binding sequence of TaDof5 was identified in the promoter of one of the TaDof5 co-expressed genes in wheat and subsequent analysis showed that TaDof5 was capable of binding to this promoter region with high affinity. These data suggest that TaDof5 may be involved in photoperiod responses associated with flowering time. TaDof4 was among a large number of previously identified growth-related genes expressed at significantly higher levels in wheat cultivars and progeny lines with high transpiration efficiency (TE) (the amount of biomass produced per unit of water transpired). Field trials were undertaken with the parents and progeny from a cross between Quarrion (high TE) and Genaro 81 (low TE) and demonstrated that the high TE progeny lines had improved early vegetative growth. TaDof4 was therefore characterised further for a role related to biomass production and/or contribution to the TE trait. Expression profiling showed that TaDof4 was consistently expressed at higher levels in the lines with high TE, constitutively expressed in major vegetative organs, drought down-regulated and sucrose up-regulated. Over-expression of TaDof4 identified one line with significantly improved biomass. DNA binding specificity analysis demonstrated that TaDof4 binds to the AAAG(T/C) core target motif essential for Dof DNA binding. These results suggest that TaDof4 is potentially associated with growth-related processes in wheat. In conclusion this study has made the following achievements: (1) identified 31 TaDof family members in Triticum aestivum, (2) used phylogenetic analysis and expression profiling to infer potential functional roles for wheat TaDof family members, (3) further characterised TaDof5 to reveal a potential role in photoperiod responses associated with flowering and elucidated its DNA-binding specificity, (4) further characterised TaDof4 to suggest a potential role in growth-related processes. These results provide fundamental molecular information that increases our understanding of the diverse biological roles of the TaDof family, particularly in growth-related physiological processes in wheat.

Orientador: Rosana do Carmo Novaes Pinto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem / Made available in DSpace on 2018-08-20T07:14:24Z (GMT). No. of bitstreams: 1 Algave_DaniellePatricia_M.pdf: 2760532 bytes, checksum: 88cec4af4afca2d855754a0a8a919232 (MD5) Previous issue date: 2012 / Resumo: Esta dissertação, que tem como objetivo central estudar as alterações de linguagem nas epilepsias, foi produzida no âmbito da Neurolinguística Discursiva (ND), área que desde a década de 80, com os primeiros trabalhos de Coudry (1986/1988), se dedica ao estudo da linguagem nas afasias e demências, em uma perspectiva sócio-histórica. A ND contrapõe-se aos discursos hegemônicos que reduzem os fenômenos complexos (como a linguagem) às explicações orgânicas e biologizantes. Embora haja inúmeros trabalhos que se dediquem ao tema das alterações linguístico-cognitivas nas epilepsias, em geral estes se limitam a descrever uma lista de sintomas, dentre os quais as alterações de linguagem (dificuldades de encontrar/selecionar palavras, produção de parafasias, dificuldades de leitura e escrita), sem, entretanto, analisá-las ou relacioná-las a outras dificuldades cognitivas (como memória e atenção) e ainda alterações psiquiátricas (como alucinações visuais e auditivas). A epilepsia afeta, na maioria das vezes, crianças e jovens, podendo acarretar atrasos na aquisição de linguagem, dificuldades de aprendizagem e, consequentemente, um comprometimento no desenvolvimento cognitivo como um todo. Os dados apresentados, obtidos em situações dialógicas com dois sujeitos - GU e MA - ou por meio de entrevistas semi-estruturadas com sujeitos adultos comprovam que as epilepsias afetam de forma significativa as atividades linguístico-cognitivas de sujeitos que tiveram o início das crises na primeira infância. Ressaltamos a importância de realizar atividades de linguagem centradas em práticas discursivas e significativas, para que sejam minimizados os comprometimentos cognitivos. Destacamos, por fim, a importância do papel mediador dos profissionais que atuam nos ambientes clínicos e escolares / Abstract: This dissertation, which has as its main goal to study language alterations in epilepsy, was produced within the Discursive Neurolinguistics (ND), an area which has been dedicated to study language alterations in aphasia and dementia in a socio-historical perspective since the 80s, with the first works of Coudry (1986/1988). ND confronts the hegemonic discourses which reduce the complex phenomena (such as language) to organic and biological explanations. Although there are innumerous studies dedicated to the theme of linguistic-cognitive alterations in epilepsy, in general they are limited to describe a list of symptoms, among which the language alterations (word finding/selecting difficulties, production of paraphasias, difficulties for reading and writing), without, however, analyzing them or relating them to other cognitive difficulties (such as memory and attention) as well as psychiatric disorders (such as visual and auditory hallucinations). Epilepsy affects mostly children and teenagers, and may cause delays in language acquisition, learning difficulties and, consequently, an impairment in cognitive development as a whole. The data presented in this dissertation, obtained in dialogic situations with two subjects - GU and MA - or by means of semi-structured interviews with adult subjects show that the epilepsy significantly affects cognitive-linguistic activities of the individuals who had the first seizures during early childhood. We emphasize the importance of conducting language activities within meaningful discursive practices, to minimize the cognitive impairment. Finally, we also emphasize the relevance of the mediating role of professionals who work in clinical and in scholar settings / Mestrado / Linguistica / Mestre em Linguística

Nowadays, more and more flexible and efficient processes are required in modern industrial applications. In this field, robots are a key technoligy. In this paper a application is considered, where a 6-axis-industrial robot has to pick-and-place objects time efficiently in a constantly changing environment. Therefore, a concept for automated motion planning is presented, which is composed of two steps which are path planning and trajectory generation. In this paper suitable and established model-based methods are analyzed and chosen. Eventually, the suitability of the presented concept for the considered task is shown by implementing the concept in Matlab and applying it to a 6-axis articulated robot arm.

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The goal of this thesis is to develop a soft multiple-degree-of-freedom (multi-DOF) load cell that is robust and light weight for use in robotics applications to sense three axes of force and a single axis of torque. The displacement of the magnet within the elastomer changes the magnetic flux density which is sensed by two 3-axis Hall effect sensors. Experimental measurements of magnetic flux density within the area of interest were used to formulate analytic expressions that relate magnet field strength to the position of the magnet. The displacement and orientation measurement and the material properties of the elastomer are used to calibrate and calculate the applied load. The ability to measure 3-DOF force and axial torque was evaluated with combined loading applied by a robotic arm (KUKA, LBR r820 iiwa). The decoupled results show the 4-DOF load cell was able to distinguish 3-axis force and 1-axis torque with 6.9% averaged error for normal force, 4.3% and 2.6% for shear force in the X and Y axis and 8.6% for the torque. The results show good accuracy for a soft multi-axis sensor that would be applicable in many robotic applications where high accuracy is not required.