Analysis of the most suitable project management approach for projects with parallel planning and execution phases

Planning projects is a key for success. In the case of projects with major investments like in aircraft maintenance related projects, it is even more indispensable. It is imperative to have total control of all variables and requirements due the enormous complexity and investment associated, which can lead to huge losses if a reliable plan is not established. This work was developed in a multinational military aviation company on the Airborne Warning and Control System Depot Level Maintenance (DLM) project. This project is characterized by parallel planning and execution phases which shows to be difficult tasks for a traditional project management approach as currently in use. The team faces issues on performing both phases at the same time, which can compromise compliance with project requirements and may decrease customer satisfaction. In order to overcome this problem, after assessing different approaches from the literature, a new approach has been developed to solve the issue that the DLM project was facing. As conclusion, the new approach turned the planning phase much more effective, which allowed to use less resources than before to perform it without interfering on the execution phase. This increased the planning performance, which will provide updated plans to the execution phase, ensuring by that way the compliance with project requirements

Desenvolvimento de sensores em fibra ótica para avaliação do desempenho e segurança de baterias de iões de lítio

Society’s dependency on fossil fuels is becoming a critical obstacle regarding environmental sustainability. The concentrated political power on institutions related to the fossil fuel market represents a worldwide energy dependence. Alternative energy sources could be explored to supply the energetic needs of human activity and better distribute the energy supply around the world. However, to be able to make use of these alternative energies is mandatory to consume them right away or to store them as potential energy, otherwise, they would be wasted. Multiple initiatives are investing and aiming to reduce the usage of fossil fuels by stimulating the research and development of alternative energy sources, together with energy storage development is crucial to potentialize the utilization and adoption of such alternative energies. Nowadays, rechargeable Li-ion batteries are the most adopted, scalable, and demanded energy storage devices in the world. The scarcity of information regarding the interior of the LiBs currently hinders the improvement of the accuracy and predicting capabilities of current battery management algorithms and models, while equally limiting attempts to refine the battery thermal design due to the absence of heat-transfer information. This has led to increasing interest in spatiotemporal imaging of the thermal flows within a cell using temperature sensors. The tracking of gas production and/or pressure variations are also very recent topics of sensing inside the LIBs. However, due to the difficulty and complexity of sensing, the integration of the sensors inside the battery cells being necessary, they were not yet so explored. In this work, hybrid optical fiber sensors based on Fabry-Perot Interferometers (FPIs) and Fiber Bragg Grating (FBG) sensors were successfully developed and characterized to discriminate two impactful parameters (pressure and temperature) internally and externally simultaneously on cylindrical lithium-ion batteries (LiB) in order to improve their operation in safety conditions. The proposed hybrid sensors consist of a photosensitive single-mode fiber (SMF), where the FBGs were inscribed and spliced to a small section of a hollow-core fiber (HCF). To create the FPI, the HCF’s tip was submerged in a UV-photosensitive polymer, creating three cavities and two observable light beam interferences in the optical spectrum, resulting in two Fabry-Perot responses. Out of four created sensors with different HCF and liquid polymer cavity’s lengths, three of them were calibrated to temperature and pressure. By tracking the FP fringes and the resulting envelope shifts of the spectral responses, it achieved higher sensitivities for the hybrid sensor with 175.86 μm and 26.38 μm of cavities’ lengths for the envelope analysis, with 31.65 nm/bar and 1.53 nm/°C, with the pressure sensitivity being the highest recorded value for this type of configuration. After calibrating steps, the hybrid sensor D was selected and embedded inside a commercial LG 18650 LiB to internally dual-parameter sensing. The placement of the FBGs and the Fabry-Perot cavity allow the detection of pressure in all battery and temperature changes near the negative and positive terminals, and in the middle of the battery during several galvanostatic cycles. Externally, were also placed one optical fiber with four FBGs to acquire external temperature variations in the outer case, being one of them outside of the case to ambient temperature control. Galvanostatic cyclic tests were performed through different temperatures, 25.0 and 40.0 °C. The online detection of the FP fringes and FBGs peaks allows, through a matrixial method discrimination, obtain the temperature and pressure variations. It resulted in successful temperature and pressure readings, resembling some occurrences presented in the available literature and other findings which concerns to pressure and temperature behaviours in different battery locations can be highlighted, like some of the thermal events were undetected by the external FBG sensors. Although some key factors need to be further studied to understand the potential of this sensor, like the long-term stability, however this hybrid sensor design has enormous potential to perform simultaneous measurements of internal pressure and temperature shifts during normal and abnormal working conditions of an 18650 LiB.A dependência da sociedade em combustíveis fósseis está a tornar-se num grande obstáculo no que toca à sustentabilidade ambiental. O poder político concentrado nas instituições relacionadas com o mercado de combustíveis fósseis representa uma dependência energética global. Fontes de energia alternativas podem ser exploradas para fornecer toda a energia da atividade humana e distribuí-la melhor pelo mundo. Todavia, para se utilizar estas energias alternativas, é necessário consumi-las imediatamente ou armazená-las como energia potencial, senão serão desperdiçadas. Múltiplas áreas estão a investir para procurar reduzir o uso de combustíveis fósseis ao estimular a investigação e o desenvolvimento de fontes de energia alternativas que, juntamente com o desenvolvimento de formas de armazenar energia, é crucial para potencializar a utilização e adoção de tais energias. Atualmente, baterias de iões de Lítio (LiBs) são as mais utilizadas, escaladas e pedidas fontes de armazenamento de energia pelo mundo. A falta de informação sobre o interior das baterias atualmente dificulta o aumento da precisão e capacidade de previsão dos atuais algoritmos e modelos dos sistemas de gestão das baterias (BMS), enquanto limita as tentativas para refinar o design térmico das baterias devido à ausência de informação sobre as transferências de calor. Isto levou ao aumento do interesse nas imagens tempo-espaciais dos fluxos térmicos dentro de uma bateria através de sensores de temperatura. O acompanhamento da variação de produção de gases e/ou de pressão são também tópicos recentes em sensores dentro de LiBs. No entanto, devido à dificuldade e complexidade de deteção, a integração dos sensores dentro de baterias, sendo necessárias, não estão a ser exploradas. Neste trabalho, sensores de fibra ótica híbridos baseados em Interferómetros Fabry-Perot (FPIs) e em redes de Bragg (FBGs) foram desenvolvidos e caraterizados com sucesso para discriminar simultaneamente dois fatores impactantes, pressão e temperatura, em LiBs cilíndricas para melhorar a sua operação em condições de segurança. O sensor híbrido proposto consiste numa fibra monomodo (SMF), onde foram gravadas FBGs, fundida com um curto segmento de tubo oco cilíndrico (HCF). Para criar o FPI, a ponta da HCF foi mergulhada num polímero líquido, fotossensível (PS) a radiação ultravioleta (UV), criando três cavidades e duas interferências visíveis no espetro ótico, resultando em duas respostas Fabry-Perot. Dos quatro sensores fabricados com diferentes comprimentos de HCF, três deles foram calibrados à temperatura e à pressão. Ao seguir a variação das franjas das respostas Fabry-Perot e dos envelopes resultantes, atingiu-se maiores sensibilidades para o sensor híbrido com 175.86 μm e 26.38 μm de comprimento das cavidades através da análise dos envelopes com 31.65 nm/bar e 1.53 nm/°C, sendo a sensibilidade à pressão o maior valor registado para sensores nesta configuração. Após a calibração, o sensor híbrido D foi selecionado e colocado dentro de uma LiB comercial LG 18650 para medir internamente os dois parâmetros. O posicionamento das FBGs e da cavidade Fabry-Perot permitem a deteção de variações de pressão no terminal positivo da bateria, e de temperatura perto dos terminais negativos e positivos, e no meio da mesma, durante os testes cíclicos galvanostáticos. Externamente, foi acrescentada uma fibra ótica com quatro FBGs para adquirir as variações de temperatura externas na cápsula protetora da bateria, sendo uma delas destinadas ao controlo da temperatura ambiente. Os testes galvanostáticos foram realizados a diferentes temperaturas, 25.0 °C e a 40.0 °C. A deteção em tempo real das franjas Fabry-Perot e dos picos das FBGs permitiu, através de um método de discriminação matricial, obter as variações de temperatura e pressão. Resultou em leituras bem-sucedidas de temperatura e pressão, apresentando comportamentos similares a descritos pela literatura e vários comportamentos referentes aos sinais de temperatura e pressão foram identificados, tal como alguns eventos térmicos que foram detetados pelas FBGs externas. Apesar de alguns fatores importantes ainda precisarem de algum aprofundamento para se avaliar o potencial deste sensor híbrido, como a estabilidade a longo termo, este sensor tem um enorme potencial para realizar medições simultâneas das variações de pressão e temperatura nas 18650 LiBs, durante os seus períodos de normal e anormal funcionamento.Mestrado em Engenharia Físic

Amazonian Maize: Diversity, Spatial Distribution and Historical-Cultural Diffusion

Subsistence is one of the factors that determined the presence or migration of prehistoric human populations. At the same time, humans were largely responsible for the dissemination of important crop plants such as maize (Zea mays). Maize is the major domesticated species in the New World, with thousands of landraces that were shaped by environment and human culture. Genetic analyses of archaeological and indigenous maize samples were used to verify the occurrence in South America of at least two major introductory waves of distinct races of maize from its center of origin in Mexico. The first occurred around 5000 years ago and spread primarily through the Andean region. The second one, 2000 years ago, spread through the lowlands of South America. These two distributions may reflect cultural isolation between the regions. In terms of subsistence, the present study found that the maize used by indigenous Brazilian populations, including those in Amazonia, is genetically closer to samples from Mexico than to samples from the Andes. This applies to both the contemporary and the archaeological samples indicating that the inhabitants of Brazil, including those from Amazonia, had a stronger relationship with populations from Central America and northern South America than from the Andean region. An exception can be seen in the region of northern Chile through Paraguay to southern Brazil, where the mixture of the three genetic groups indicates possible cultural contact between highland and lowland peoples. Additionally, the greatest diversity in maize was observed in samples from Roraima state, in northern Amazonia, and this may reflect the fact that human populations of the region had intense contact with different cultural groups, including the Andean groups

Domestication and Dispersal of Native Crops in Amazonia

Recent decades have witnessed the rapid expansion of interest in and research on the domestication of crop plants worldwide. These species are the basis of the rise to dominance of Homo sapiens over the last 10,000 years. New techniques in archaeology and the expansion of molecular genetics are uncovering abundant evidence to support or refute old hypotheses about human domestication of crops and creation of food production systems that fueled population expansions and linguistic diasporas, and to raise new hypotheses. In Amazonia and elsewhere in lowland South America, archaeologists are starting to examine these hypotheses in earnest, and geneticists are starting to generate data to identify crop origins and dispersals. Archaeologists now generally agree that Amazonia was inhabited by numerous advanced societies before European conquest, especially along the major white water rivers and in other favorable locations for food production, and that these societies had domesticated significant areas of numerous landscapes. This special section of Tipití summarizes a set of presentations given during the recent 2nd International Meeting on Amazonian Archaeology, held in Manaus, Amazonas, in September 2010. An overview of plant domestication opens the sequence, followed by new archaeobotanical evidence from the southeastern Colombian and central Brazilian Amazonia and from the southern savannas of Brazil, and new molecular genetic evidence about the origins of peach palm (Bactris gasipaes) and the dispersal of manioc (Manihot esculenta), maize (Zea mays), and peach palm in lowland South America

Pequenas notas sobre a noção de estilo na física

Ao longo do século XX, a noção de estilo se estabeleceu como uma categoria quase necessária dentro do campo da estética. Tal fato, aliado à completa flexibilidade de significado do termo, fez com que seu uso se expandisse para diversos campos. Dada essa versatilidade, parece apenas natural que logo essa noção seria usada para estudar as ciências. O que nos propomos é pensar um pouco sobre a sua aplicabilidade dentro do campo das ciências, mais especificamente da física.  O caminho a ser traçado será apresentar alguns casos nos quais estilo aparece dentro desse contexto, seja da física, seja do conhecimento como um todo. Por fim, discutiremos alguns aspectos gerais que parecem ser necessários no desenvolvimento de uma estilística da física e da prática científica.&nbsp

Material arqueológico para o estudo de evolução de plantas cultivadas

This research studies archaeological samples of maize (Zea mays mays) and cassava (Manihot esculenta), from Januaria, MG, Brazil, for samples between 1010 (for the oldest sample) and 570 years (for the most recent) as estimated through radiocarbon dating. Maize cobs were morphologically analysed by using length, basal and apical diameters, largest diameter, number of rows, number of grains per row, and number of grains per row per length parameters. The maize cob length presented increases through time, allowing an increase on the number of seed per cob, but the size of seeds did not vary significantly. Starch present in the reserve organs of the maize and cassava were analysed morphologically through Scanning Electron Microscopy, and compared to indigenous and modern samples, aiming to estimate the diversity of the material and, for the cassava, to assure that samples were truely Manihot sp. The starch of the maize and cassava reserve organs was in excellent state of conservation and the morphology of the starch grains allowed the separation of maize varieties. More than one variety of maize was found on a same period of time, suggesting that the old indigenous people of the area planted different varieties of maize simultaneously and these varieties changed through the studied period of time. Finally archaeological starch grains of maize presented more diverse standards than modern grains.Amostras arqueológicas de milho (Zea mays mays) e mandioca (Manihot esculenta), oriundas da região de Januária, Minas Gerais, Brasil, com idades estimadas entre 1010 anos para a amostra mais antiga, até 570 anos para as mais novas, foram estudadas morfologicamente. No caso do milho, tomaram-se medidas de comprimento da espiga, diâmetro basal, diâmetro apical, diâmetro maior, número de fileiras, número de grãos por fileiras e número de grãos por fileiras por comprimento. O tamanho da espiga aumentou com o tempo, permitindo aumento da quantidade de sementes, mas sem que estas sementes sofressem uma variação significativa em seu tamanho. Amostras de grãos de amido das sementes de milho e do tubérculo de mandioca foram estudados por meio de microscopia eletrônica de varredura e comparadas com amostras de raças indígenas e etnovariedades, para estimar a diversidade deste material e, no caso do tubérculo, para certificação que se tratava realmente de mandioca e não uma outra espécie. O amido dos órgãos de reserva do milho e mandioca encontram-se em excelente estado de conservação e, através da morfologia dos grãos de amido foram separadas raças ou variedades de milho. Constatou-se a presença de mais de uma raça de milho em um mesmo período de tempo e estas raças foram variando ao longo do período analisado (de 1010 a 570 anos atrás). A variabilidade dos grãos de amido das amostras arqueológicas de milho se apresentou maior do que as amostras atuais utilizadas

The notion of language deviations in St. Augustine’s Ars pro fratrum mediocritate breuiata

The notion of linguistic correction (Latinitas) with which Augustine of Hippo introduced his Ars pro fratrum mediocritate breuiata seems central to the philosopher's grammatical discussion, not only because of the various examples that Augustine offers about the definitions of barbarism and soloecism at the end of this treatise, but also because the subject of correction (Latinitas) and, consequently, of the deviations of language (barbarismus and soloecismus), are also presented in other non-grammatical works: The confessions, De ordine and De doctrina Christiana. In this article, we propose to evaluate the conceptual outlines of the notions of barbarism and solecism in the work of Augustine, considering, on the one hand, the definitions present in the Ars breuiata, and, on the other, the way in which Augustine also presents them in his philosophical work. We propose that the normative orientation contained in the text of ars must be relativised by ethical questions that arise from the comments present in the Confessions, the De ordine and the De doctrina Christiana

Analysis of relationship between retraction and muscular strength in individuals of specific populations

The aim of this study was to verify the relationship between the degree of retraction and the muscular force in individuals of specific populations. Volunteers of the masculine gender, with age between 17 and 46 years old, were divided in four groups: GI (Sedentary, n=11); GII (Musculation, n=11); GIII (Worker, n=9); GIV (Worker + Musculation - n=10). Tests of retraction in the muscular groups of the shoulder had been evaluated, in knee and posterior chain. The palms grip strength was measured by dynamometry, was held to test the arm bending, strength of quadriceps, hamstrings and chest. In the results to degrees of flexibility for adduction of the shoulder, the group GIV (143.79º ± 8.71) had to be significantly higher than the group GIII (122.87º ± 11.87) to the right side (R). GIII (117.26º ± 9.05), in turn, showed lower compared to GII (131.06º ± 17.47) group for the left (L) (p\u3c0.05). To rotators of shoulder muscles, there was significant difference, with lower values for the group GIII (81.22º ± 8.63), compared to GII (98.65º ± 13.40), to the R side, and GIII (75.00º ± 7.05) compared the GI (98.15º ± 7.68) and GII (93.82º ± 19.00), side L (p\u3c0.01). The chain later muscle points higher ranges in centimeters for the GIV (5.32 ± 4.71) compared to the group GI (1.00 ± 5.02) (p\u3c0.01). For bending the arm and holds palm forests, the gains went to musculation athletes of individuals in relation to groups without weight training. Therefore, the practice of exercises of weight training does not seem important to the development of permanent muscle shortening to individuals, enabling greater power generation in individuals that practice