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No / Abstract: The scarcity of frequency spectrum used for wireless communication systems has attracted a considerable amount of attention in recent years. The cognitive radio (CR) terminology has been widely accepted as a smart platform mainly aimed at the efficient interrogation and utilization of permitted spectrum. Non-parametric spectrum sensing, or estimation, represents one of the prominent tools that can be proposed when CR works under an undetermined environment. As such, the periodogram, filter bank, and multi-taper methods are well considered in many studies without relying on the transmission channel's characteristics. A unified approach to all these non-parametric spectrum sensing techniques is presented in this paper with analytical and performance comparison using simulation methods. Results show that the multi-taper method outperforms the others.

Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-04-30T22:39:20Z No. of bitstreams: 1 DISS_2015_Ariel Souza Rossi.pdf: 2445630 bytes, checksum: 83e29452e738e684605b37aae31b6bb3 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-05-16T14:56:01Z (GMT) No. of bitstreams: 1 DISS_2015_Ariel Souza Rossi.pdf: 2445630 bytes, checksum: 83e29452e738e684605b37aae31b6bb3 (MD5) / Made available in DSpace on 2018-05-16T14:56:01Z (GMT). No. of bitstreams: 1 DISS_2015_Ariel Souza Rossi.pdf: 2445630 bytes, checksum: 83e29452e738e684605b37aae31b6bb3 (MD5) Previous issue date: 2015-06-19 / O objetivo desta pesquisa consistiu em ajustar um modelo de fator de forma e modelo de afilamento para Pinus caribaea var. caribaea Barr. et Golf. para a região Centro-Sul de Mato Grosso. O povoamento localizado no município de Nova Marilândia possui área de 215,47ha, e o seu entorno é ocupado por atividades agrícolas. A implantação foi efetuada com mudas de origem seminal e o povoamento não recebeu qualquer tratamento silvicultural e os dados foram coletados em 2014, quando o povoamento possuía 36 anos. A descrição do povoamento ocorreu através de um inventário aleatório, visando representar todo o povoamento. Posteriormente foi realizada a classificação sociológica do povoamento de acordo com a metodologia de Hozokawa e Souza. Os dados coletados são provenientes de 90 árvores, oriundas de todas as classes sociológicas. Para o ajuste do fator de forma foram testados 10 modelos e para o ajuste do afilamento foram testados os modelos de Kozak, Polinômio de Potências Fracionárias e Hradetzky. Além disso, foram comparados os volumes obtidos através do fator de forma e através da integral da função de afilamento com o volume obtido através da cubagem rigorosa. Dentre os modelos de fator de forma avaliados, o que melhor ajustou aos dados foi um modelo logarítmico; o modelo de Hradetzky apresentou melhor ajuste ao afilamento e calculou mais precisamente o volume total. A comparação dos volumes estimados e o calculado, ao nível de 5% (α = 0,05) para o teste de Tukey não foi verificada diferença estatisticamente significativa. / The aim of this research consisted adjust a model of factor of form and model of afilamento caribaea Pinus to var. caribaea Barr. et Golf. for the region Center-South of Mato Grosso. The population located in the city of Nova Marilândia possesses area of 215,47ha, and around is occupied for agricultural activities. The implantation was performed with seedlings of seminal origin, the population did not receive any silvicultural treatment and the data were collected in 2014, when the population had 36 years. The description of the population occurred through a random inventory, aiming at to represent the population all. Subsequently the sociological classification of the population was carried in accordance with the methodology of Hozokawa and Souza. The collected data are proceeding from 90 trees, deriving of all the sociological classes. For the adjustment of the form factor 10 models were tested and for the adjustment of the tapering, the models of Kozak, Polynomial of Powers Fracionárias and Hradetzky, were tested. Moreover, the volumes obtained through the factor of form and the integral of the tapper function were compared with the volume obtained through the rigorous cubage. Amongst the models of form factor evaluated, what better it adjusted to the data was a logarithmic model; the model of Hradetzky presented adjustment to the tapering better and calculated the total volume more precisely. The comparison of the estimated volumes and the calculated one, to the level of 5% (α = 0,05) for the test of Tukey was not verified statistically significant difference.

Syftet med studien var att undersöka hur Ultra Short Race Pace Training (USRPT) uppfattas från tränares perspektiv. Uppsatsen jämför även metoden med taper och en mer traditionell träningsmetod. Studien baseras på 12 intervjuer med tränare som arbetat med junior/senior-simmare och en litteratursökning för att kunna besvara frågeställningarna. Vidare analyseras det genom teorin praxisgemenskap och metoden kvalitativ innehållsanalys. Resultatet visar att USRPT är en högintensiv metod som uppfattas olika av simtränare men att den utvecklar den anaeroba kapaciteten och inte den aeroba. Skillnader och likheter mellan USRPT, taper och mera traditionella metoder kan enligt studien mätas på två skalor bestående av intensitet och volym. Det påvisades av tränare att USRPT och taper kan ha samma volym men att det förstnämnda är mer intensivt. / The aim of this study was to examine how Ultra Short Race Pace Training (USRPT) is being perceived by swim coaches. It also compared the method with taper and a more traditional approach to swim training. The study was based on 12 interviews with swim coaches who have worked with junior/senior-swimmers and a literature search to be able to answer the questions. Furthermore, it was analyzed through with the theory community of practice and the method qualitative content analysis. The results showed that USRPT is a high-intensity method that is perceived differently by different coaches but develops the anaerobic capacity and not the aerobic capacity. The differences and similarities between USRPT, taper and a more traditional approach could, according to the study, be measured on two different scales. These are intensity and volume. It was pointed out by swim coaches that USRPT and taper could have the same volume, but that the first-mentioned is more intense.

Este trabalho teve por objetivo desenvolver e caracterizar um sensor de força utilizando uma fibra óptica modificada pelo processo conhecido como Fiber tapering. A fibra quando modificada deixa exposto o campo evanescente, o que a torna sensível a influências externas, e a luz guiada na fibra pode vir a sofrer reflexão interna total frustrada ao entrar em contato com materiais. Ao envolver a região modificada por um material elastomérico, a área de contato e consequentemente a atenuação torna-se uma função da intensidade da força aplicada, possibilitando então relacionar a força a atenuação da luz. Baseando-se nesse efeito, foi criado um sensor de dimensões reduzidas, de rápida resposta, linear, altamente sensível e de boa repetibilidade. Foi criado também um circuito eletrônico utilizando amplificadores operacionais para a aquisição e processamento do sinal proveniente da fibra e selecionado um sensor comercial comum para a realização de experimentos e comparações. Ambos os sensores foram posicionados sobre uma balança de precisão e submetidos a diversos esforços obtendo-se dados sobre a resposta estática. Em seguida utilizando um shaker eletrodinâmico foram medidos os tempos de resposta a uma entrada degrau, e realizando esforços repetitivos foram analisados os desvios das medidas lidas pelos sensores. / The aim of this research was to develop and characterize a force sensor using a modified optical fiber by a process known as Fiber tapering. The modified fiber leaves the evanescent field exposed and prone to external influences and the guided light may suffer frustration of total internal reflection upon contact with materials. When covering the modified fiber section with an elastomeric material, the contact area and therefore the attenuation becomes a function of the applied pressure, making it possible to relate force to attenuation in light intensity. Based on this effect, a small sensor was created, having a quick response time, with high linearity, high sensitivity and good repeatability. Along with the sensor, an electronic circuit using operational amplifiers was designed for acquisition and processing of the signal obtained from the optical fiber. In addition, in order to perform experiments and comparisons, a standard force sensor was chosen. Both sensors were placed over a precision weighing scale and had different intensities of force applied on them, and after that, data regarding static measurements was gathered. The response time was obtained using an electrodynamic shaker and applying a step input. Furthermore, data was gathered about the deviations on the measurements by performing a repetitive set of compressions.

Os implantes cone morse apresentam um travamento e vedamento por meio de atrito entre as paredes do implante e do pilar protético. Nos sistemas convencionais do tipo Hexágono externo e interno, para reduzir o afrouxamento dos parafusos protéticos, são utilizados materiais de cobertura de superfície, como carbono e ouro. Não foram encontradas referências na literatura da utilização desse tipo de deposição em componentes do sistema cone morse. O propósito desse estudo é mensurar, registrar e avaliar os valores do torque de desaperto em pilares protéticos dos tipos sólido e parafuso passante do sistema cone morse com a deposição de carbono na zona de atrito do pilar protético. Foram utilizados 40 implantes cone morse com seus respectivos pilares divididos em 4 grupos (n=10): G1- pilar sólido; G2- pilar sólido com deposição de carbono na zona de atrito do sistema morse; G3- estudo somente do parafuso do pilar passante; G4- estudo somente do parafuso do pilar passante com deposição de carbono na ponta ativa; G5- estudo somente do pilar passante sem ação do parafuso; G6- estudo somente do pilar passante revestido em carbono na zona de atrito do sistema morse sem ação do parafuso. Cada pilar recebeu uma seqüência de 5 apertos e desapertos (20Ncm para o pilar sólido e 10Ncm para o parafuso passante). Os resultados mostraram no teste estatístico ANOVA para dois fatores de variação (desaperto e carbono), haver diferença estatística significante entre os grupos: G1 maior que G2 (p < 0,01); G4 maior que G3 (p < 0,01); G6 maior que G5 (p < 0,01). Esse estudo concluiu que o grupo controle G1 mostrou maior valor através da media aritmética (23,706 Ncm) em relação ao grupo experimental G2 (22,114 Ncm); o grupo experimental G4 mostrou maior valor através da media aritmética (8,218 Ncm) em relação ao grupo controle G3 (7,354 Ncm) e o grupo experimental G6 mostrou maior valor através da media aritmética (10,268 Ncm) em relação ao grupo controle G5 (6,906 Ncm), mostrou também que não houve diferença significativa (p > 0,01) para o fator desaperto em todos os grupos estudados, ou seja, não houve interferência da deformação do material com a repetição dos ciclos de aperto e desaperto. / The morse taper implants present a locking and sealing by means of the attrition between implants internal walls and the abutment. In the external and internal conventional hexagon system, to reduce the prosthetic screw loosing, its used covering surface materials, as carbon and gold. Literature reference using these kind of surface deposition were not found in morse taper abutment implants. The aim of this study is to measure, register and evaluate the removal torque values in morse taper solid abutment and passing screw abutment with carbon deposition in attrition zone. They were used 40 morse taper implants with their respective abutments divided in 4 groups (n = 10): G1 solid abutment; G2 - solid abutment with carbon deposition in attrition zone; G3 evaluation only in the screw of the passing abutment; G4 - evaluation only in the screw of the passing abutment with carbon deposition in the screw thread; G5 - evaluation only in the passing abutment without the screw action; G6 - evaluation only in the passing abutment with carbon deposition in attrition zone without the screw action. Each abutment received a sequence of 5 tightening and removal torque (20Ncm in solid abutment and 10Ncm in passant screw abutment). The results of ANOVA statistic test for two factors of variation (removal torque and carbon), showed that there is significant statistic difference between the groups: G1 higher than G2 (p < 0.01); G4 higher than G3 (p < 0.01); G6 higher than G5 (p < 0.01). This study concluded that control group G1 showed a higher value through the arithmetical media (23.706Ncm) in relation of the experimental group G2 (22.114Ncm); the experimental group G4 showed higher value through the arithmetical media (8.218Ncm) in relation of the control group G3 (7.354Ncm) and the experimental group G6 showed higher values through the arithmetical media (10.268Ncm) in relation of the control group G5 (6.906Ncm), and also showed that there was not significant difference (p < 0.01) to the removal torque factor in all the groups studied, that is, there was not a material deformation interference with the tightening and removal torque cycles repetition.

Os implantes cone morse apresentam um travamento e vedamento por meio de atrito entre as paredes do implante e do pilar protético. Nos sistemas convencionais do tipo Hexágono externo e interno, para reduzir o afrouxamento dos parafusos protéticos, são utilizados materiais de cobertura de superfície, como carbono e ouro. Não foram encontradas referências na literatura da utilização desse tipo de deposição em componentes do sistema cone morse. O propósito desse estudo é mensurar, registrar e avaliar os valores do torque de desaperto em pilares protéticos dos tipos sólido e parafuso passante do sistema cone morse com a deposição de carbono na zona de atrito do pilar protético. Foram utilizados 40 implantes cone morse com seus respectivos pilares divididos em 4 grupos (n=10): G1- pilar sólido; G2- pilar sólido com deposição de carbono na zona de atrito do sistema morse; G3- estudo somente do parafuso do pilar passante; G4- estudo somente do parafuso do pilar passante com deposição de carbono na ponta ativa; G5- estudo somente do pilar passante sem ação do parafuso; G6- estudo somente do pilar passante revestido em carbono na zona de atrito do sistema morse sem ação do parafuso. Cada pilar recebeu uma seqüência de 5 apertos e desapertos (20Ncm para o pilar sólido e 10Ncm para o parafuso passante). Os resultados mostraram no teste estatístico ANOVA para dois fatores de variação (desaperto e carbono), haver diferença estatística significante entre os grupos: G1 maior que G2 (p < 0,01); G4 maior que G3 (p < 0,01); G6 maior que G5 (p < 0,01). Esse estudo concluiu que o grupo controle G1 mostrou maior valor através da media aritmética (23,706 Ncm) em relação ao grupo experimental G2 (22,114 Ncm); o grupo experimental G4 mostrou maior valor através da media aritmética (8,218 Ncm) em relação ao grupo controle G3 (7,354 Ncm) e o grupo experimental G6 mostrou maior valor através da media aritmética (10,268 Ncm) em relação ao grupo controle G5 (6,906 Ncm), mostrou também que não houve diferença significativa (p > 0,01) para o fator desaperto em todos os grupos estudados, ou seja, não houve interferência da deformação do material com a repetição dos ciclos de aperto e desaperto. / The morse taper implants present a locking and sealing by means of the attrition between implants internal walls and the abutment. In the external and internal conventional hexagon system, to reduce the prosthetic screw loosing, its used covering surface materials, as carbon and gold. Literature reference using these kind of surface deposition were not found in morse taper abutment implants. The aim of this study is to measure, register and evaluate the removal torque values in morse taper solid abutment and passing screw abutment with carbon deposition in attrition zone. They were used 40 morse taper implants with their respective abutments divided in 4 groups (n = 10): G1 solid abutment; G2 - solid abutment with carbon deposition in attrition zone; G3 evaluation only in the screw of the passing abutment; G4 - evaluation only in the screw of the passing abutment with carbon deposition in the screw thread; G5 - evaluation only in the passing abutment without the screw action; G6 - evaluation only in the passing abutment with carbon deposition in attrition zone without the screw action. Each abutment received a sequence of 5 tightening and removal torque (20Ncm in solid abutment and 10Ncm in passant screw abutment). The results of ANOVA statistic test for two factors of variation (removal torque and carbon), showed that there is significant statistic difference between the groups: G1 higher than G2 (p < 0.01); G4 higher than G3 (p < 0.01); G6 higher than G5 (p < 0.01). This study concluded that control group G1 showed a higher value through the arithmetical media (23.706Ncm) in relation of the experimental group G2 (22.114Ncm); the experimental group G4 showed higher value through the arithmetical media (8.218Ncm) in relation of the control group G3 (7.354Ncm) and the experimental group G6 showed higher values through the arithmetical media (10.268Ncm) in relation of the control group G5 (6.906Ncm), and also showed that there was not significant difference (p < 0.01) to the removal torque factor in all the groups studied, that is, there was not a material deformation interference with the tightening and removal torque cycles repetition.

Este trabalho teve por objetivo desenvolver e caracterizar um sensor de força utilizando uma fibra óptica modificada pelo processo conhecido como Fiber tapering. A fibra quando modificada deixa exposto o campo evanescente, o que a torna sensível a influências externas, e a luz guiada na fibra pode vir a sofrer reflexão interna total frustrada ao entrar em contato com materiais. Ao envolver a região modificada por um material elastomérico, a área de contato e consequentemente a atenuação torna-se uma função da intensidade da força aplicada, possibilitando então relacionar a força a atenuação da luz. Baseando-se nesse efeito, foi criado um sensor de dimensões reduzidas, de rápida resposta, linear, altamente sensível e de boa repetibilidade. Foi criado também um circuito eletrônico utilizando amplificadores operacionais para a aquisição e processamento do sinal proveniente da fibra e selecionado um sensor comercial comum para a realização de experimentos e comparações. Ambos os sensores foram posicionados sobre uma balança de precisão e submetidos a diversos esforços obtendo-se dados sobre a resposta estática. Em seguida utilizando um shaker eletrodinâmico foram medidos os tempos de resposta a uma entrada degrau, e realizando esforços repetitivos foram analisados os desvios das medidas lidas pelos sensores. / The aim of this research was to develop and characterize a force sensor using a modified optical fiber by a process known as Fiber tapering. The modified fiber leaves the evanescent field exposed and prone to external influences and the guided light may suffer frustration of total internal reflection upon contact with materials. When covering the modified fiber section with an elastomeric material, the contact area and therefore the attenuation becomes a function of the applied pressure, making it possible to relate force to attenuation in light intensity. Based on this effect, a small sensor was created, having a quick response time, with high linearity, high sensitivity and good repeatability. Along with the sensor, an electronic circuit using operational amplifiers was designed for acquisition and processing of the signal obtained from the optical fiber. In addition, in order to perform experiments and comparisons, a standard force sensor was chosen. Both sensors were placed over a precision weighing scale and had different intensities of force applied on them, and after that, data regarding static measurements was gathered. The response time was obtained using an electrodynamic shaker and applying a step input. Furthermore, data was gathered about the deviations on the measurements by performing a repetitive set of compressions.

Magister Chirurgiae Dentium - MChD / When faced with a failing or failed root treatment, the dentist must decide whether the tooth can be retreated and saved or extracted. The dentist's decision to retreat is often based on the x-ray presenting a failing root treatment. The dentist must be aware that there might be a number of factors that have contributed to the failure and which may preclude, following retreatment, a successful long term clinical function. The current study has been made to determine those factors that may influence the prognosis in order to assist the clinician in advising the patient of the best course of treatment. A literature review was made to determine and identify these factors and explain their relevance and influence on the healing process. The current study included identifying the factors described in the literature review and noting their influence on the prognosis following non-surgical retreatment. Retreatment of failed root treated teeth requires special knowledge and skill from the clinician in order to correct and manage the case. The current study was made in a clinical setting and compared results of retreatment with two types of rotary files on the market: progressive or variable taper (Pro Taper) with constant non-ISO 06 taper (K3). Clinical signs and symptoms were noted at the patient's presentation and following recalls at 1, 4 months and 1 year. The results were recorded and statistically analysed and the results were discussed. The results showed that out of 81 patients 10cases of retreatment were considered to have failed and 68 cases were considered to have been successful. Three patients did not return for their assessments and were therefore not considered in further results. There was a statistically significant (p<0.1 0) recording of deep periodontal pockets associated with teeth with failing root treatments (40%) and (13%) in the "Success" group. The two estimated proportions of "Sinus" present (60%) in the "Failure" group and 10% in the 'Success' group were significantly different (p<0.01). "Sinus present" in the "Success group" means in the initial clinical assessment before retreatment was initiated. The presence of a sinus at the One Year follow up signified a failure of the root retreatment (p<0.001). The two estimated proportions of "Occlusion" present (80% and 99%) in the "Failure" and "Success" group were significantly different (p<0.05). Therefore, teeth in "occlusion" were more within the "Success" group. 70% of those teeth that failed had pretreatment apical rarefactions of greater than 6mm diameter; whereas 76.5% of successful retreatments had areas less than 6mm diameter. The differences were significant according to Fisher's Exact Test (p<0.01). 44% of failed cases had areas of rarefaction described as "diffuse"; and 56% of failed cases had areas that were described as "well-defined". 95% of cases that were successful had areas described as "diffuse" and the rest were "welldefined". The differences between the success and failure categories were statistically significant (p<0.0 1). The two estimated proportions of "Post present" (0% and 31%) in the "Failure" and "Success" groups were significantly different (p<0.1 0). Therefore, the "Post was present" in many more cases within the "Success" group than in the "Failure" group. There was no difference between the Median "Crown/Root" ratios of the "Failure" (Median = 0.595) or "Success" groups (Median = 0.662) (Wilcoxon Test, p>O.10). Teeth with longer roots tend to lead to failure, however there was a considerable overlap between the distributions. Therefore the finding is that the Median length of the roots of the "Failures" is longer than that of the "Successes". (Wilcoxon Rank Sum Test, p-value = 0.0628). The results also indicated that previous short root filling preparation contributes to the final success of retreatment (Fisher Exact Test, p<0.05). There was a significant difference between the distribution of the "Failure" and "Success" (88.2%) groups (Fisher Exact Test, p<O.OI) in those cases with initial short obturated fillings. When comparing the outcome following the use of the two types of rotary files it was found that the "Successes" with K3 File (35 out of 41) was 85%; and with Protaper File (32 out of 36) 89%. The "Success" rate certainly was not different between the two file types. The conclusions drawn from the current study was not significantly different from those in the literature review and the overall results were of a similar nature with some minor changes. However it is clear that non-surgical root retreatment offers a good prognosis and should be included as an option for failed or failing root treatment.

Heartwood is the dead, inner layers of wood in the tree which no longer transport water. It is usually dark in colour and has increased decay-resistance compared to the sapwood. Heartwood forms in the transition zone when the ray cells die and deposit chemical extractives in the surrounding xylem. These chemicals convey natural durability which is of value to the forest and timber industry. Despite its value the formation of heartwood is poorly understood. The objective of this PhD is to improve our understanding of heartwood formation in Sitka spruce and Scots pine, the most widely planted species in Britain. Separating heartwood and sapwood at the sawmill can increase timber value due to differences in wood properties. The amount of heartwood varies both with height within, and between trees. Empirical models were developed to describe heartwood and sapwood distribution by diameter, area and ring number 1) within any wood disc 2) with height in the standing tree using taper functions, and 3) its variation between trees. Models will be incorporated into wood quality models to optimise heartwood utilisation. According to pipe theory a certain area of sapwood sustains a volume of canopy, with redundant sapwood converted to heartwood. Sap flux was examined across the sapwood and transition zone in Sitka spruce to understand water transport in relation to heartwood formation and identify seasonal change in transport in the transition zone. Results suggest that the transition zone ceases water transport around dormancy and the amount of heartwood formed may be driven by new wood formation, maintaining sapwood depth. Heartwood formation is a seasonal process, however this has not been confirmed in Sitka spruce or Scots pine, or under UK climatic conditions. Seasonal variation in carbon dioxide and ethylene production by the transition zone were measured to identify the time of heartwood formation, which was late summer through dormancy, consistent with published literature. The role of ethylene in heartwood formation is confirmed. Heartwood formation is an active developmental process, a form of programmed cell death, and as such must be carefully regulated temporally and spatially. Regulation by phytohormones has been proposed but not confirmed. Screening for a broad range of phytohormones during the proposed season of heartwood formation identified an increase in abscisic acid and a decrease in auxin concentration in the transition zone. Abscisic acid, auxin and ethylene also regulate xylogenesis, therefore the same signals that initiate cambial dormancy may also provide the temporal regulation of heartwood formation. The results of this PhD will optimise the use of heartwood in Sitka spruce and Scots pine in the UK and contribute towards selective tree breeding for increased heartwood volume worldwide.