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Submitted by Jorge Cativo (jorge.cativo@inpa.gov.br) on 2018-08-23T16:19:05Z No. of bitstreams: 2 Dissertação-ClarissaFontes_versão_final.pdf: 1535750 bytes, checksum: 0708a48068415e0b31a364d392d9d2f5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-08-23T16:19:05Z (GMT). No. of bitstreams: 2 Dissertação-ClarissaFontes_versão_final.pdf: 1535750 bytes, checksum: 0708a48068415e0b31a364d392d9d2f5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2012-04-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / We analyzed the causes and temporal distribution of tree mortality in 10 ha of an old growth forest located in E.E.S.T / INPA, Manaus, Amazonas. The study aimed to 1) reveal the main causes of tree death and 2) describe the variation in mortality over the year and also correlates it with climatic variables. The study was conducted in two transects of 20 x 2,500 m (5 ha each) and all individuals with DBH ≥ 10 cm were sampled, totaling 5,808 trees. The transects were monitored every month, alternately, for a year. The sanitary condition of living trees was observed in each monitoring. The dead individuals were classified according to their mode of death (standing, broken or uprooted). The pre and post-death of the trees were analyzed in order to identify the cause of the death. During one year of monitoring, 67 individuals died or 6.7 trees / ha and the mortality rate was 1.15%. year-1. Of the 67 dead trees, 24 died uprooted, 23 broken and 20 standing dead. Mortality was highly correlated with the rates of monthly rainfall (r = 0.85). Therefore, the events of death are more frequent in the rainy season. The correlation between mortality and wind speed was not as strong as expected (r = - 0.29) and the direction of the individuals fall was random. Altogether were distinguished six categories of cause of tree death. Storms (rain + wind) was the main cause, accounting for 45% of deaths. Close behind was stress and biotic factors, killing 20 of the 67 dead individuals. Of these 20 trees, at least one was killed by liana Apuí and 3 died from infestation by pathogenic fungi. The results indicate that from the small intervals between monitoring is possible to determine the cause of trees death in tropical forests and elucidate the effect of seasonal variations on mortality. The work has generated new information to the Amazon and it is suggested that these studies are included in the projects of forest dynamics. / Foi analisado as causas e a distribuição temporal da mortalidade arbórea em 10 ha de floresta não perturbada localizada na E.E.S.T/INPA, Manaus, Amazonas. O estudo teve como objetivo 1) revelar as principais causas da morte arbórea e 2) descrever a variação da mortalidade ao longo do ano além de correlaciona-la com variáveis climáticas. O trabalho foi conduzido em dois transectos de 20 x 2.500m (5 ha cada) e todos os indivíduos arbóreos com DAP ≥ 10cm foram amostrados, somando 5.808 árvores. Os transectos foram monitorados todos os meses durante um ano de forma alternada. O estado fitossanitário das árvores vivas foi observado em cada uma das medições. Os indivíduos mortos foram classificados de acordo com seu modo de morte (em pé, quebrado ou desenraizado). As condições pré e pós-morte das árvores foram analisadas com a finalidade de se identificar a causa da sua morte. Durante um ano de monitoramento, morreram 67 indivíduos ou 6,7 árvores/ha e a taxa de mortalidade calculada foi de 1,15%.ano-1. Das 67 árvores mortas, 24 morreram desenraizadas, 23 mortas em pé e 20 mortas quebradas. A mortalidade foi altamente correlacionada com as taxas de precipitação mensal (r = 0,85). Portanto, os eventos de morte são mais frequentes na estação chuvosa. A correlação entre mortalidade e velocidade máxima mensal do vento foi fraca e negativa (r = -0,3) e a direção de queda dos indivíduos foi aleatória. Ao todo se determinou seis categorias de causa de morte arbórea. As tempestades (chuva + vento) foram a principal causa, responsável por 45% das mortes. Logo atrás das tempestades veio a causa estresse e fatores bióticos, matando 20 dos 67 indivíduos mortos. Dessas 20 árvores, pelo menos uma foi morta por cipó Apuí e 3 morreram por infestação de fungos patogênicos. Os resultados indicam que a partir dos pequenos intervalos entre as remedições é possível determinar as causas de morte arbórea nas florestas tropicais, além de elucidar o efeito das variações sazonais sobre a mortalidade. O trabalho gerou informações inéditas para a Amazônia e sugerese que esses estudos sejam inseridos nos projetos de monitoramento da dinâmica florestal.

Steroid hormones and receptors play a role in regulating biological events underlying brain development and sexual differentiation. Current evidence indicates that circulating sex steroid hormones are not entirely responsible for development of neural sex differences in song birds such as the zebra finch. p68, as a coactivator specific for estrogen receptor alpha (ERα) and an essential factor in early tissue development and maturation might play a role in sexual differentiation. Zebra finches have a sexually dimorphic song control nuclei in the brain, males have larger song nuclei than females, and are ideal model for investigating the mechanisms controlling sexual differentiation of the brain and behavior. Western blot analysis showed a significant sex difference at post hatch day 10 (P10). Immunohistochemistry showed localization of p68 immunoreactive cells in the ZF brain including nuclei that compose the avian song system. p68 is probably developmentally regulated and may be modulated by endogenous estrogen and estrogen receptors suggesting a role for p68 in sexual differentiation. INDEX WORDS: p68, coactivator, RNA helicase, steroid receptor, song control nuclei, zebra finch (ZF)

This dissertation documents alternative designs of the Zero Forcing decoding algorithm with Successive Interference Cancellation (ZF-SIC) for use in Vertical Bell Laboratories Layered Space Time Architecture (V-BLAST) Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) systems, in an effort to reduce the computational complexity of the receiver. The development of a wireless platform utilizing this architecture intended for use in an indoor wireless multipath environment was created to analyze the multipath environment. This implementation is the result of efforts from several individuals within the CST group. My contributions are documented in this dissertation. In order to obtain channel state information (CSI), a training sequence is sent with each incoming frame. A pseudo-inverse operation is performed on the channel matrix and applied to each OFDM symbol that was received. Performing this operation on each tone and across each OFDM symbol is computationally inefficient in a MIMO configuration. If the number of pseudo-inverses can be reduced while maintaining acceptable levels of bit error, the processing time of each frame can be decreased. Traditionally, tests of the performance of ZF-SIC have been conducted with simulations modelling a multipath channel. In this thesis, CSI is observed using an open loop platform developed for MIMO-OFDM communications. The rate of change of the channel is observed for different multipath environments. The proposed methods of decoding require modifications to ZF-SIC. The suggested changes are only applicable to a MIMO OFDM based method of data transmission. The most effective method of reducing decoding complexity and maintaining an acceptable number of bit errors was observed to occur in the time domain rather than in the frequency domain. For selecting frames and averaging frames in the time domain it was determined that the optimal number of OFDM symbols per frame is 1932 and 174, respectively.

Massive multiple-input-multiple-output (MM) is becoming a promising candidate for wireless communications. The idea behind MM is to use a very large number of antennas to increase throughput and energy efficiency by one or more orders of magnitude. In order to make MM feasible, many challenges remain. In the uplink a fundamental question is whether to deploy single massive arrays or to build a virtual array using cooperative base stations. Also, in such large arrays the signal processing involved in receiver combining is non-trivial. Therefore, low complexity receiver designs and deployment scenarios are essential aspects of MM and the thesis mainly focuses on these two areas. In the first part, we investigate three deployment scenarios: (i) a massive co-located array at the cell center; (ii) a massive array clustered at B discrete locations; and (iii) a massive distributed array with a uniform distribution of individual antennae. We also study the effect of propagation parameters, system size, correlation and channel estimation error. We demonstrate by analysis and simulation that in the absence of any system imperfections, a massive distributed array is preferable. However, an intermediate deployment such as a massive array clustered at a few discrete locations can be more practical to implement and more robust to imperfect channel state information. We then focus on the performance of the co-located scenario with different types of antenna array, uniform square and linear arrays. With MM, it may be the case that large numbers of antennas are closely packed to fit in some available space. Hence, channel correlations become important and therefore we investigate the space requirements of different array shapes. In particular, we evaluate the system performance of uniform square and linear arrays by using ergodic capacity and capacity outage. For a range of correlation models, we demonstrate that the uniform square array can yield similar performance to a uniform linear array while providing considerable space saving. In the second part of the thesis we focus on low complexity receiver designs. Due to the high dimension of MM systems there is a considerable interest in detection schemes with a better complexity-performance trade-off. We focus on linear receivers (zero forcing (ZF) and maximum ratio combining (MRC)) used in conjuction with a Vertical Bell Laboratories Layered Space Time (V-BLAST) structure. Our first results show that the performance of MRC V-BLAST approaches that of ZF V-BLAST under a range of imperfect CSI levels, different channel powers and different types of arrays as long as the channel correlations are not too high. Subsequently, we propose novel low complexity receiver designs which maintain the same performance as ZF or ZF V-BLAST. We show that the performance loss of MRC relative to ZF can be removed in certain situations through the use of V-BLAST. The low complexity ordering scheme based on the channel norm (C-V-BLAST) results in a V-BLAST scheme with MRC that has much less complexity than a single ZF linear combiner. An analysis of the SINR at each stage of the V-BLAST approach is also given to support the findings of the proposed technique. We also show that C-V-BLAST remains similar to ZF for more complex adaptive modulation systems and in the presence of channel estimation error, C-V-BLAST can be superior. These results are analytically justified and we derive an exhaustive search algorithm for power control (PC) to bound the potential gains of PC. Using this bound, we demonstrate that C-V-BLAST performs well without the need for additional PC. The final simplification is based on the idea of ordering users based on large scale fading information rather than instantaneous channel knowledge for a V-BLAST scheme with MRC (P-V-BLAST). An explicit closed form analysis for error probability for both co-located and distributed BSs is provided along with a number of novel performance metrics which are useful in designing MM systems. It is shown that the error performance of the distributed scenario can be well approximated by a modified version of a co-located scenario. Another potential advantage of P-V-BLAST is that the ordering can be obtained as soon as the link gains are available. Hence, it is possible that mean SINR values could be used for scheduling and other link control functions. These mean values are solely functions of the link gains and hence, scheduling, power adaptation, rate adaptation, etc. can all be performed more rapidly with P-V-BLAST. Hence, the P-V-BLAST structure may have further advantages beyond a lower complexity compared to C-V-BLAST.

This dissertation documents alternative designs of the Zero Forcing decoding algorithm with Successive Interference Cancellation (ZF-SIC) for use in Vertical Bell Laboratories Layered Space Time Architecture (V-BLAST) Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) systems, in an effort to reduce the computational complexity of the receiver. The development of a wireless platform utilizing this architecture intended for use in an indoor wireless multipath environment was created to analyze the multipath environment. This implementation is the result of efforts from several individuals within the CST group. My contributions are documented in this dissertation. In order to obtain channel state information (CSI), a training sequence is sent with each incoming frame. A pseudo-inverse operation is performed on the channel matrix and applied to each OFDM symbol that was received. Performing this operation on each tone and across each OFDM symbol is computationally inefficient in a MIMO configuration. If the number of pseudo-inverses can be reduced while maintaining acceptable levels of bit error, the processing time of each frame can be decreased. Traditionally, tests of the performance of ZF-SIC have been conducted with simulations modelling a multipath channel. In this thesis, CSI is observed using an open loop platform developed for MIMO-OFDM communications. The rate of change of the channel is observed for different multipath environments. The proposed methods of decoding require modifications to ZF-SIC. The suggested changes are only applicable to a MIMO OFDM based method of data transmission. The most effective method of reducing decoding complexity and maintaining an acceptable number of bit errors was observed to occur in the time domain rather than in the frequency domain. For selecting frames and averaging frames in the time domain it was determined that the optimal number of OFDM symbols per frame is 1932 and 174, respectively.

This master's thesis deals with the issue of the treatment of grape marcs and other biodegradable wastes originating in agricultural activities as suitable raw materials for composting. In the literary part are described the individual input raw materials and the composting process. The basis for the experimental part was the proposing of four variants of recipes with different proportions of grape marcs and their subsequent verification in composting practice. At the same time, both of survey in the areas under cultivation and a balance of biodegradable waste generated at the Faculty of Horticulture, Mendel University in Brno were conducted. From the information obtained, the size of the area needed for setting up an experimental composting plant was calculated and the costs of production of 1 tonne of compost was determined.

Rapid development processes and higher customer requirements lead to increasing integration of software solutions in the automotive industry’s products. Today, several electronic control units communicate by bus systems like CAN and provide computation of complex algorithms. This increasingly requires a controlled timing behavior. The following diploma thesis investigates how the timing analysis tool SymTA/S can be used in the software development process of the ZF Friedrichshafen AG.Within the scope of several scenarios, the benefits of using it, the difficulties in using it and the questions that can not be answered by the timing analysis tool are examined

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Modern day technology aspires to always progress. This progression leads to a lot of research in any significant area of improvement. There is a growing amount of end-users in the wireless spectrum which has led to a need for improved bandwidth usage and BER values. In other words, new technologies which would increase the capacity of wireless systems are proving to be a crucial point of research in these modern times. Different combinations of multiuser receivers are evaluated to determine performance under normal working conditions by comparing their BER performance charts. Multiple input, multiple output (MIMO) systems are incorporated into the system to utilise the increased capacity rates achievable using the MIMO configuration. The effect of MIMO on the technologies associated with modern day technological standards such as CDMA and OFDM have been investigated due to the significant capacity potentials these technologies normally exhibit in a single antenna scenario. An in-depth comparison is established before comparison is made with a conventional maximum likelihood (ML) detector. The complexity of the ML detector makes its realization evaluated in such a manner to achieve the same or near ML solution but with lower computational complexity. This was achieved using a proposed modification of the Schnorr-Euchner Sphere decoding algorithm (SE-SDA). The proposed sphere decoder (P-SD) adopts a modification of the radius utilised in the SE-SDA to obtain a near ML solution at a much lower complexity compared to the conventional ML decoder. The P-SD was configured to work in different MIMO antenna configurations. The need for the highest possible data rates from the available limited spectrum led to my research into the multi-user detection scenario and MIMO.