O objetivo deste trabalho é analisar a relação entre práticas de governança corporativa e desempenho de 370 empresas brasileiras de capital aberto no período de 1997 a 2007. O banco de dados utilizado foi construído a partir de dados extraídos dos relatórios Informativos Anuais (IAN), fornecidos pela Comissão de Valores Mobiliários (CVM) e pela base de dados do Economática®. Para considerar a causalidade reversa entre as variáveis de governança e desempenho e tendo em vista a presença de endogeneidade, utilizou-se um sistema de equações simultâneas composto por quatros equações. Neste sistema as variáveis de governança corporativa, estrutura de capital, estrutura de propriedade e desempenho foram consideradas endógenas. Os parâmetros do modelo foram estimados com a utilização do método de mínimos quadrados de dois estágios (MQ2E) e de mínimos quadrados de três estágios (MQ3E). O teste de Hausman sugere que as estimativas obtidas por meio de mínimos quadrados de três estágios são mais apropriadas para as inferências estatísticas. Os principais resultados indicaram que a diferença entre o direito de voto e o direito de fluxo de caixa em posse do maior acionista último é negativamente relacionada com o desempenho operacional da empresa. Isto indica que empresas com maior potencial de expropriação dos acionistas minoritários pelos majoritários tendem a apresentar menor desempenho. Esse resultado confirma a hipótese de que uma maior qualidade de governança corporativa impacta positivamente no desempenho da firma. Com a utilização da metodologia empregada, também foi possível analisar a influência do desempenho da firma sobre aspectos de governança corporativa. Os resultados apontaram que, quanto maior o desempenho maior a diferença entre o direito de voto e direito de fluxo de caixa do maior acionista último. Assim, os resultados evidenciam que a adoção de práticas de governança é importante para explicar o desempenho da firma, e também indicam a existência de inter-relação entre as variáveis testadas no modelo. / The objective of this study is to analyze the relationship between corporate governance practices and performance of 370 Brazilian companies traded in the period of 1997 to 2007. The used data base was created from extracted data of Informative Annual reports (IAN), provided by Comissão de Valores Mobiliários (CVM) and by the data base of Economática®. To consider the reverse causality between governance variables and performance and in view of the presence of endogeneity, we used a system of simultaneous equations consisting of four equations. In this system, the corporate governance variables, capital structure, ownership structure and performance were considered endogenous. The model parameters were estimated using the method of two-stage least squares (2SLS) and three-stage least squares (3SLS). The Hausman test suggests that the obtained estimates through the tree-stage least squares are more appropriate for statistical inferences. The main results indicate that the difference between voting right and cash flow right at the possession of the last largest shareholder is negatively related to the company\'s operating performance. This result indicates that firms with greater potential for expropriation of minority shareholders by majority shareholders tend to have lower performance which confirms the hypothesis that a higher quality of corporate governance has a positive impact on firm performance. Using this methodology, it was also possible to analyze the influence of the firm performance on aspects of corporate governance. The results support that, the higher the performance the greater the difference between voting rights and cash flow right to the last major shareholder. Thus, the results indicate that the adoption of governance practices is important to explain the performance and also indicate the existence of inter-relationship between the studied variables.

This thesis focuses on the theory and implementation of visual navigation techniques for Autonomous Air Vehicles in outdoor environments. The target of this study is to fuse and cooperatively develop an incremental map for multiple air vehicles under the application of Simultaneous Location and Mapping (SLAM). Without loss of generality, two unmanned air vehicles (UAVs) are investigated for the generation of ground maps from current and a priori data. Each individual UAV is equipped with inertial navigation systems and external sensitive elements which can provide the possible mixture of visible, thermal infrared (IR) image sensors, with a special emphasis on the stereo digital cameras. The corresponding stereopsis is able to provide the crucial three-dimensional (3-D) measurements. Therefore, the visual aerial navigation problems tacked here are interpreted as stereo vision based SLAM (vSLAM) for both single and multiple UAVs applications. To begin with, the investigation is devoted to the methodologies of feature extraction. Potential landmarks are selected from airborne camera images as distinctive points identified in the images are the prerequisite for the rest. Feasible feature extraction algorithms have large influence over feature matching/association in 3-D mapping. To this end, effective variants of scale-invariant feature transform (SIFT) algorithms are employed to conduct comprehensive experiments on feature extraction for both visible and infrared aerial images. As the UAV is quite often in an uncertain location within complex and cluttered environments, dense and blurred images are practically inevitable. Thus, it becomes a challenge to find feature correspondences, which involves feature matching between 1st and 2nd image in the same frame, and data association of mapped landmarks and camera measurements. A number of tests with different techniques are conducted by incorporating the idea of graph theory and graph matching. The novel approaches, which could be tagged as classification and hypergraph transformation (HGTM) based respectively, have been proposed to solve the data association in stereo vision based navigation. These strategies are then utilised and investigated for UAV application within SLAM so as to achieve robust matching/association in highly cluttered environments. The unknown nonlinearities in the system model, including noise would introduce undesirable INS drift and errors. Therefore, appropriate appraisals on the pros and cons of various potential data filtering algorithms to resolve this issue are undertaken in order to meet the specific requirements of the applications. These filters within visual SLAM were put under investigation for data filtering and fusion of both single and cooperative navigation. Hence updated information required for construction and maintenance of a globally consistent map can be provided by using a suitable algorithm with the compromise between computational accuracy and intensity imposed by the increasing map size. The research provides an overview of the feasible filters, such as extended Kalman Filter, extended Information Filter, unscented Kalman Filter and unscented H Infinity Filter. As visual intuition always plays an important role for humans to recognise objects, research on 3-D mapping in textures is conducted in order to fulfil the purpose of both statistical and visual analysis for aerial navigation. Various techniques are proposed to smooth texture and minimise mosaicing errors during the reconstruction of 3-D textured maps with vSLAM for UAVs. Finally, with covariance intersection (CI) techniques adopted on multiple sensors, various cooperative and data fusion strategies are introduced for the distributed and decentralised UAVs for Cooperative vSLAM (C-vSLAM). Together with the complex structure of high nonlinear system models that reside in cooperative platforms, the robustness and accuracy of the estimations in collaborative mapping and location are achieved through HGTM association and communication strategies. Data fusion among UAVs and estimation for visual navigation via SLAM were impressively verified and validated in conditions of both simulation and real data sets. / © Cranfield University, 2013

M.A. (Applied Linguistics) / Much research has focused on general strategy use during simultaneous interpreting (SI), while little research has been conducted on how interpreters’ choice of strategies relates to source text (ST) delivery speed (DS). Hence, it is unclear whether interpreters use the same strategies when confronted with fast speech, average speech, and slow speech; or, whether they use different strategies under these three conditions. This research argues that interpreters use specific strategies to cope with the different ST delivery speed during simultaneous interpreting within the Pan-African Parliament (PAP). The PAP consists of delegates from African countries with different linguistic and cultural backgrounds. In order to facilitate communication in this multilingual setting, the PAP has adopted six official working languages. However, the latter still do not resolve institutional communication barriers; hence the need for such services as simultaneous interpreting. The PAP is situated in Midrand, South Africa, and plays an important role in African politics. It offers SI in English and French. Nevertheless, no previous studies on simultaneous interpreting have been conducted at the PAP. Thus, through empirical research based on primary data consisting of recordings of simultaneous interpreting in French and English at the PAP, this study examines interpreters’ use of strategies. The main focus of the study is the strategies for fast, average, and slow delivery speed identified by Gile (1995), during actual interpreting at the PAP The study categorises these interpreting strategies into meaning-based (lexical dissimilarity) or form-based (lexical similarity) and indicates those that are more appropriate for each DS during SI. By differentiating the various strategies used by interpreters to deal with all three ST delivery speeds, this study creates an awareness about and clarifies how certain interpreting conditions, such as speed, affect interpreters’ coping tactics. In particular, the study demonstrates that the faster the speed, the more form-based (FB) the strategies will be; and, the slower the speed, the more interpreters will resort to meaning-based (MB) strategies. Ultimately, the study demonstrates that strategies that lead to meaning-based interpreting are more successful than the others which lead to a form-based interpreting.

Šárka Timarová: Pracovní paměť v konferenčním simultánním tlumočení disertační práce Abstrakt Tato disertační práce se zaměřuje na otázku zapojení pracovní paměti v procesu konferenčního tlumočení. Pracovní paměť je pro simultánní tlumočení považována za klíčový kognitivní mechanismus, ale toto tvrzení zatím nebylo významně empiricky podloženo. Předkládaná studie vychází z teoretické literatury jak v oblasti tlumočení, tak v oblasti kognitivní psychologie. Analýza publikovaných empirických prací ukázala několik mezer v současném bádání, a to především skutečnost, že výzkum se dosud soustředil pouze na některé funkce pracovní paměti (především funkce paměťové) a na testování osob bez tlumočnické praxe či s praxí omezenou (studenti tlumočení). Předkládaná studie pojímá pracovní paměť šířeji se zvláštním zřetelem k funkcím řídícím, které úzce souvisejí s pozorností, a dále se zaměřuje výlučně na profesionální tlumočníky. Podstatou studie je srovnání výkonu tlumočníků v testech pracovní paměti a při simultánním tlumočení. Výsledky ukazují, že a) existuje vztah mezi pracovní pamětí tlumočníků a simultánním tlumočením, b) tento vztah se týká především funkcí řídících; u funkcí paměťových se žádný zásadní vztah neprokázal, c) některé funkce pracovní paměti se rozvíjejí spolu s tlumočnickou praxí, a d) vztah...

Although biological phenomena may be partially described in a general way without the use of mathematics and physics, the experimental results may be more meaningful if they are analyzed on the basis of physical and mathematical laws . The complexity of biological systems has made the application to them of mathematics and physics rather difficult, and only recently has much progress been made . Although it has yet been possible to describe only a few simple biological systems by actual equations, a great deal of qualitative information may be obtained by applying physics and mathematics. Russell (1960, p. 439) said In principle at least, the properties and processes of living plants may be described by the terminology and laws of physics. Such properties as color, mass, volume, area, viscosity, elasticity, specific heat, and permeability; and such processes as diffusion, reflection, osmosis, heat conduction, fluid flow, absorption, and swelling are examples of physical concepts useful in describing living plants.

Knowledge of water and salt movement in soils is necessary for development of a management scheme for controlling the quality of irrigation return flow. A computer model was developed to predict the distribution of water and salts in the root zone under varying initial and boundary conditions. The model consists of water flow and salt flow sub-models. The water flow sub-model considers the numerical approximation of the general water flow equation with modification for water loss by evapotranspiration (and thus root extraction). The salt flow sub-model considers the mass flow of salts, chemical exchange, precipitation or dissolution of CaCO3, and CaSO4, and formation of undissociated Ca and Mg sulphate. The model was tested under laboratory and field conditions by comparing predicted values with experimental measurements. Satisfactory agreement was noted for the water content distribution in almost all the experiments. The model yielded approximately correct values of total salt distribution in the field and one of the column experiments. The agreement between the measured and predicted values for the two other column experiments was poor. The poor agreement seems to result from the irregular dissolution of the applied powdered salts. The distribution of individual ions was not accurately predicted by the model. The disagreement between the predicted and measured values was large at high salt concentration. Complex ion formation, insufficient description of exchange and activity coefficients at high salt concentration are suggested for this lack of agreement. Further development and field testing of the model are needed.

This dissertation proposes autonomous robotic strategies for urban search and rescue (USAR) which are map-based semi-autonomous robot navigation and fully-autonomous robotic search, tracking, localization and mapping (STLAM) using a team of robots. Since the prerequisite for these solutions is accurate robot localization in the environment, this dissertation first presents a novel grid-based scan-to-map matching technique for accurate simultaneous localization and mapping (SLAM). At every acquisition of a new scan and estimation of the robot pose, the proposed technique corrects the estimation error by matching the new scan to the globally defined grid map. To improve the accuracy of the correction, each grid cell of the map is represented by multiple normal distributions (NDs). The new scan to be matched to the map is also represented by NDs, which achieves the scan-to-map matching by the ND-to-ND matching. In the map-based semi-autonomous robot navigation strategy, a robot placed in an environment creates the map of the environment and sends it to the human operator at a distant location. The human operator then makes decisions based on the map and controls the robot via tele-operation. In case of communication loss, the robot semi-autonomously returns to the home position by inversely tracking its trajectory with additional optimal path planning. In the fully-autonomous robotic solution to USAR, multiple robots communicate one another while operating together as a team. The base station collects information from each robot and assigns tasks to the robots. Unlike the semi-autonomous strategy there is no control from the human operator. To further enhance the efficiency of their cooperation each member of the team specifically works on its own task. A series of numerical and experimental studies were conducted to demonstrate the applicability of the proposed solutions to USAR scenarios. The effectiveness of the scan-to-map matching with the multi-ND representation was confirmed by analyzing the error accumulation and by comparing with the single-ND representation. The applicability of the scan-to-map matching to the real SLAM problem was also verified in three different real environments. The results of the map-based semi-autonomous robot navigation showed the effectiveness of the approach as an immediately usable solution to USAR. The effectiveness of the proposed fully- autonomous solution was first confirmed by two real robots in a real environment. The cooperative performance of the strategy was further investigated using the developed platform- and hardware-in-the-loop simulator. The results showed significant potential as the future solution to USAR. / Ph. D.

The brain is composed of multiple systems that interact during cognition and behavior. Concurrently performing two or more tasks that compete for processing from a common system resource typically results in decremented performance, referred to as interference, for one or more of the tasks as compared to single-task performance. This interference is a hallmark of the dual-task experimental design. The purpose of this experiment is to investigate the involvement of cerebellar cortex in trace eyeblink conditioning by utilizing the traditional dual-task design. Timed-interval finger tapping, a motor function mediated by the cerebellar cortex, and several different cognitive tasks representing dissociable distributed brain memory systems were co-administered with trace eyeblink conditioning. If cerebellar cortex is involved in trace eyeblink conditioning, then timed-interval finger tapping should significantly interfere with acquisition rate for conditioned responding. Performance variables from trace eyeblink conditioning were analyzed to investigate interference effects of timed-interval finger tapping and the various cognitive tasks. Results from a series of mixed model repeated measures ANOVAs indicate that the acquisition rate and magnitude of trace conditioning was not significantly reduced in the timed-interval tapping group compared to the control group, although participants did demonstrate evidence of inferior learning. This finding suggests that cerebellar cortex is not critically involved during acquisition of trace conditioning, however it is to be interpreted with caution as methodological and theoretical confounds may preclude a straightforward conclusion. / Psychology

This dissertation describes the development of a method for simultaneous localization and mapping (SLAM)algorithm which is suitable for high dimensional vehicle and map states. The goal of SLAM is to be able to navigate autonomously without the use of external aiding sources for vehicles. SLAM's combination of the localization and mapping problems makes it especially difficult to solve accurately and efficiently, due to the shear size of the unknown state vector. The vehicle states are typically constant in number while the map states increase with time. The increasing number of unknowns in the map state makes it impossible to use traditional Kalman filters to solve the problem- the covariance matrix grows too large and the computational complexity becomes too overwhelming. Particle filters have proved beneficial for alleviating the complexity of the SLAM problem for low dimensional vehicle states, but there is little work done for higher dimensional states. This research provides an Gaussian Mixture Model based alternative to the particle filtering SLAM methods, and provides a further partition that alleviates the vehicle state dimensionality problem with the standard particle filter. A SLAM background and basic theory is provided in the early chapters. A description of the new algorithm is provided in detail. Simulations are run demonstrating the performance of the algorithm, and then an aerial SLAM platform is developed for further testing. The aerial SLAM system uses a RGBD camera as well as an inertial measurement unit to collect SLAM data, and the ground truth is captured using an indoor optical motion capture system. Details on image processing and specifics on the inertial integration are provided. The performance of the algorithm is compared to a state of the art particle filtering based SLAM algorithm, and the results are discussed. Further work performed while working in the industry is described, which involves SLAM for adding transponders onto long-baseline acoustic arrays and stereo-inertial SLAM for 3D reconstruction of deep-water sub-sea structures. Finally, a neatly packaged production line version of the stereo-inertial SLAM system presented.

Former researches provide evidence that invasive species could alter ecosystem’s components, threaten native species and cause economic losses in southern forest lands. The objective of the project is to explore significant driving factors and develop geospatial models for monitoring, predicting and mapping the extent and conditions of major invasive species. In the study area, 16 invasive species were classified into four groups: regionally spreading species, regionally establishing species, locally spreading species and regionally colonizing species by population size and spatial characteristics. According to local Moran’s I, spatial autocorrelation existed in 16 invasive species. Autologistic model and simultaneous autoregressive model were employed to explore the relationships between spatial distribution and a set of indentified variables for Chinese privet, kudzu, Nepalese browntop and tallow tree at plot and county levels. The project showed that human-caused disturbances and forest types were significantly related to the spatial distribution of four invasive species in different scales.