910 resultados para principe local-global


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This thesis studies mobile robotic manipulators, where one or more robot manipulator arms are integrated with a mobile robotic base. The base could be a wheeled or tracked vehicle, or it might be a multi-limbed locomotor. As robots are increasingly deployed in complex and unstructured environments, the need for mobile manipulation increases. Mobile robotic assistants have the potential to revolutionize human lives in a large variety of settings including home, industrial and outdoor environments.

Mobile Manipulation is the use or study of such mobile robots as they interact with physical objects in their environment. As compared to fixed base manipulators, mobile manipulators can take advantage of the base mechanism’s added degrees of freedom in the task planning and execution process. But their use also poses new problems in the analysis and control of base system stability, and the planning of coordinated base and arm motions. For mobile manipulators to be successfully and efficiently used, a thorough understanding of their kinematics, stability, and capabilities is required. Moreover, because mobile manipulators typically possess a large number of actuators, new and efficient methods to coordinate their large numbers of degrees of freedom are needed to make them practically deployable. This thesis develops new kinematic and stability analyses of mobile manipulation, and new algorithms to efficiently plan their motions.

I first develop detailed and novel descriptions of the kinematics governing the operation of multi- limbed legged robots working in the presence of gravity, and whose limbs may also be simultaneously used for manipulation. The fundamental stance constraint that arises from simple assumptions about friction and the ground contact and feasible motions is derived. Thereafter, a local relationship between joint motions and motions of the robot abdomen and reaching limbs is developed. Baseeon these relationships, one can define and analyze local kinematic qualities including limberness, wrench resistance and local dexterity. While previous researchers have noted the similarity between multi- fingered grasping and quasi-static manipulation, this thesis makes explicit connections between these two problems.

The kinematic expressions form the basis for a local motion planning problem that that determines the joint motions to achieve several simultaneous objectives while maintaining stance stability in the presence of gravity. This problem is translated into a convex quadratic program entitled the balanced priority solution, whose existence and uniqueness properties are developed. This problem is related in spirit to the classical redundancy resoxlution and task-priority approaches. With some simple modifications, this local planning and optimization problem can be extended to handle a large variety of goals and constraints that arise in mobile-manipulation. This local planning problem applies readily to other mobile bases including wheeled and articulated bases. This thesis describes the use of the local planning techniques to generate global plans, as well as for use within a feedback loop. The work in this thesis is motivated in part by many practical tasks involving the Surrogate and RoboSimian robots at NASA/JPL, and a large number of examples involving the two robots, both real and simulated, are provided.

Finally, this thesis provides an analysis of simultaneous force and motion control for multi- limbed legged robots. Starting with a classical linear stiffness relationship, an analysis of this problem for multiple point contacts is described. The local velocity planning problem is extended to include generation of forces, as well as to maintain stability using force-feedback. This thesis also provides a concise, novel definition of static stability, and proves some conditions under which it is satisfied.

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My dissertation is the first project on the Haitian Platform for Advocacy for an Alternative Development- PAPDA, a nation-building coalition founded by activists from varying sectors to coordinate one comprehensive nationalist movement against what they are calling an Occupation. My work not only provides information on this under-theorized popular movement but also situates it within the broader literature on the postcolonial nation-state as well as Latin American and Caribbean social movements. The dissertation analyzes the contentious relationship between local and global discourses and practices of citizenship. Furthermore, the research draws on transnational feminist theory to underline the scattered hegemonies that intersect to produce varied spaces and practices of sovereignty within the Haitian postcolonial nation-state. The dissertation highlights how race and class, gender and sexuality, education and language, and religion have been imagined and co-constituted by Haitian social movements in constructing ‘new’ collective identities that collapse the private and the public, the rural and the urban, the traditional and the modern. My project complements the scholarship on social movements and the postcolonial nation-state and pushes it forward by emphasizing its spatial dimensions. Moreover, the dissertation de-centers the state to underline the movement of capital, goods, resources, and populations that shape the postcolonial experience. I re-define the postcolonial nation-state as a network of local, regional, international, and transnational arrangements between different political agents, including social movement actors. To conduct this interdisciplinary research project, I employed ethnographic methods, discourse and textual analysis, as well as basic mapping and statistical descriptions in order to present a historically-rooted interpretation of individual and organizational negotiations for community-based autonomy and regional development. ^

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An important episode of carbon sequestration, Oceanic Anoxic Event 1a (OAE-1a), characterizes the Lower Aptian worldwide, and is mostly known from deeper-water settings. The present work of two Lower Aptian deposits, Madotz (N Spain) and Curití Quarry (Colombia), is a multiproxy study that includes fossil assemblages, microfacies, X-ray diffraction bulk and clay mineralogy, elemental analyses (major, minor, trace elements), Rock-Eval pyrolysis, biomarkers, inorganic and organic carbon content, and stable carbon isotopes. The results provide baseline evidence of the local and global controlling environmental factors influencing OAE-1a in shallow-water settings. The data also improve our general understanding of the conditions under which organic-carbon-rich deposits accumulate. The sequence at Madotz includes four intervals (Unit 1; Subunits 2a, 2b and 2c) that overlap the times prior to, during and after the occurrence of OAE-1a. The Lower Unit 1(3m thick) is essentially siliciclastic, and Subunit 2a (20m) contains Urgonian carbonate facies that document abruptly changing platform conditions prior to OAE-1a. Subunit 2b (24.4 m) is a mixed carbonate-siliciclastic facies with orbitolinid-rich levels that coincides with OAE-1a δ13C stages C4-C6, and is coeval with the upper part of the Deshayesites forbesi ammonite zone. Levels with pyrite and the highest TOC values (0.4-0.97%), interpreted as accumulating under suboxic conditions, and are restricted to δ13C stages C4 and C5. The best development of the suboxic facies is at the level representing the peak of the transgression. Subunit 2c, within δ13C stage C7, shows a return of the Urgonian facies. The 23.35-m section at Curití includes a 6.3-m interval at the base of the Paja Formation dominated by organic-rich marlstones and shales lacking benthic fossils and bioturbation, with TOC values as high as 8.84%. The interval overlies a level containing reworked and phosphatized assemblages of middle Barremian to lowest Aptian ammonites. The range of values and the overall pattern of the δ13Corg (-22.05‰ to -20.47‰) in the 6.3m-interval is comparable with Lower Aptian δ13C stage C7. Thus, conditions of oxygen depletion at this site also occurred after Oceanic Anoxic Event-1a, which developed between carbon isotope stages C3 and C6. Both sites, Madotz and Curití, attest to the importance of terrigenous and nutrient fluxes in increasing OM productivity that led to episodic oxygen deficiency.

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Portugal’s manufacturing sector has a significant importance both in national income and employment. As has been pointed out by several researchers, the traditional methods of analysis fail to grasp all the dimensions of economic competitiveness. This dissertation is then, at its core, an analysis of Portugal’s manufacturing industry in terms of the latter’s value added to production and impact to employment under the framework of global value chains. The current dissertation seeks to study in which way the Portuguese manufacturing industry, and its respective sectors, has a direct and indirect impact on the creation of value added and employment and how this impact can be measured. For development of this work the input-output approach for calculation of multipliers and the new framework proposed by Timmer et al. (2013) for calculation of GVC income and GVC jobs indicators were used, elaborated on the basis of the WIOD project dataset. Moreover, to illustrate the application of the provided methodology the Portuguese textile industry was used as an example. It was found that the changes in final demand of such sectors as Pulp, Paper, Printing and Publishing; Machinery, Nec and Textiles and Textile Products would have a larger impact on generated value added than other manufacturing sectors. At the same time, employment created by the changes in final demand would be more impacted by such sectors as Food, Beverages and Tobacco; Wood and Products of Wood and Cork and Textiles and Textile Products. In this regard, the number of low-skilled workers in Portugal seems to be more effected by changes in final demand, than those occupied by higher -skilled individuals. Moreover, it was found that the distribution of GVC income and GVC jobs for the Portuguese manufacturing industry shares a similar outlook. However, upon closer inspection of GVC labour distribution by skill levels there seems to exist a general progression in which low-skilled jobs requirements are met by local resources, while the need for higher skilled jobs require a greater “off-shoring” of work The results obtained through calculations of presented multipliers provide a powerful tool for policy makers in strategic planning of development of national economy. Using the provided methodology and obtained results, a government and supranational organizations could define which industry would have the greatest impact for an additional unit of output generated through the economy, and thus define the sectors for further investments.

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In a globalized economy, the use of natural resources is determined by the demand of modern production and consumption systems, and by infrastructure development. Sustainable natural resource use will require good governance and management based on sound scientific information, data and indicators. There is a rich literature on natural resource management, yet the national and global scale and macro-economic policy making has been underrepresented. We provide an overview of the scholarly literature on multi-scale governance of natural resources, focusing on the information required by relevant actors from local to global scale. Global natural resource use is largely determined by national, regional, and local policies. We observe that in recent decades, the development of public policies of natural resource use has been fostered by an “inspiration cycle” between the research, policy and statistics community, fostering social learning. Effective natural resource policies require adequate monitoring tools, in particular indicators for the use of materials, energy, land, and water as well as waste and GHG emissions of national economies. We summarize the state-of-the-art of the application of accounting methods and data sources for national material flow accounts and indicators, including territorial and product-life-cycle based approaches. We show how accounts on natural resource use can inform the Sustainable Development Goals (SDGs) and argue that information on natural resource use, and in particular footprint indicators, will be indispensable for a consistent implementation of the SDGs. We recognize that improving the knowledge base for global natural resource use will require further institutional development including at national and international levels, for which we outline options.

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Goncalo de Melo Bandeira Counter-Terrorism, State of Emergency and Human Rights. In the global cities, the fight against terrorism is a way forward. Prevention of terrorism is another possible way. There are legal systems where the prevailing idea is combating terrorism. Fight, because is possible: life imprisonment or informal death penalty or even torture. While other jurisdictions only follow the prevention of terrorist crime: the retribution and positive general prevention and the resocialization. There may be extreme cases also in restorative justice. The recent terrorist attacks in Paris on 11.13.2015 have shown to the different types of police several problems. Some of those are: the declaration of State of emergency and the consequent restriction of human rights as the privacy of human communication or the liberty of travel by local city citizens or foreign citizens or the public entertainment shows, the problem of money laundering and the restriction of the business as usual, the vicious circle of more isolation from some urban communities, v.g. muslims, and other citizens also; and, brevitatis causa, the criminological problem of the causes and consequences of terrorism.

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Abstract : OBJECTIVES : Canadian medical (MD), physiotherapy (PT) and occupational therapy (OT) students increasingly show an interest in global health experiences (GHEs). As certain moral hazards can occur as a result of student GHEs, a growing consensus exists that universities must have an established selection process, in-depth pre-departure training (PDT), adequate onsite supervision and formal debriefing for their students. This study aimed at identifying current practices in Canadian MD, PT and OT programs and discussing areas for improvement by comparing them with recommendations found in the literature. METHODS : Canadian MD, PT and OT programs (n = 45) were invited to answer an online survey about their current practices for GHE support and training. The survey included 24 close-ended questions and 18 open-ended questions. Descriptive statistics and a thematic analysis were performed on the data and results were discussed with recommendations found in the literature. RESULTS : Twenty-three programs responded to the survey. Student selection processes varied across universities; examples included using academic performance, interviews and motivation letters. All but 1 MD program had mandatory PDT; content and teaching formats varied, as did training duration (2-38 hours). All but 1 MD program had onsite supervision; local clinicians were frequently involved. Debriefing, although not systematic, covered similar content; debriefing was variable in duration (1-8 hours). CONCLUSIONS : Many current practices are encouraging but areas for improvement exist. Integrating global health content into the regular curriculum with advanced study option in global health for students participating in GHEs could help universities standardize support and training.

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Estimates of global sea-level change rates based on observations from Tide Gauges (TGs) show a long-term global mean sea-level rise (GMSLR) of 1÷2 mm/yr for the 20th century. The considerable scatter in these estimates is mainly attributable to the uneven distribution of the TG sites and to several physical phenomena that cause local sea level to deviate from the global mean, or to affect the TG record through land subsidence or uplift. The main cause of vertical ground motion on a regional space scale is the response of the Earth to past ice loads, called Glacial Isostatic Adjustment (GIA), which is often modelled and corrected for. In this work, a simple average approach was used to revisit two past estimates based on small sets of long, high-quality TG records in view of the longer record available, employing a newer GIA model (ICE-6G) from Peltier et al. [2015]. The value of GMSLR obtained from both sets is (1.5±0.4) mm/yr. In addition, a much larger set of TGs was used to estimate the contemporary (post 1993) GMSLR using satellite estimates from Cazenave et al. [2018] as a benchmark, in an attempt to understand how a simple average approach could perform for larger sets. The resulting estimate of (3.4÷3.5)±0.2 mm/yr (depending on the GIA correction applied) is comparable to the satellite result of (3.1±0.3) mm/yr.

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Diabetes mellitus do tipo 2 é uma doença metabólica complexa, multifatorial e de presença global, que afeta a qualidade e o estilo de vida dos acometidos, podendo levar a uma redução pronunciada na expectativa de vida dessa população. Portadores de diabetes podem ter uma redução de 15 ou mais anos de vida, com a grande maioria morrendo em decorrência das complicações cardiovasculares. Dessa forma, criou-se o objetivo de elaborar um plano de ação de intervenção a ser implantado pela equipe de saúde para prevenir complicações do Diabetes mellitus e incidência do mesmo. O método utilizado foi o Planejamento Estratégico Situacional. Foi realizado por meio desse estudo, uma avaliação do Diabetes mellitus nas áreas de abrangência: Palmital, Pau D'olinho, Forquilha e Ribeirão dos Santos pertencentes ao município Minas Novas e das dificuldades encontradas pelos profissionais da Saúde na prevenção e tratamento desta doença crônico-degenerativa, buscando profundar nos conhecimentos sobre esta situação e propor estratégias para melhor prevenção da mesma. Após o estudo pode-se afirmar que há uma alta incidência do Diabetes mellitus na área, os doentes. Além, do pouco conhecimento dos fatores de risco para a doença e que há necessidade de projeto de intervenção de saúde e conscientização da comunidade considerando que há pouca preparação da equipe de saúde para o enfrentamento da realidade.

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We have previously demonstrated that blockade of β-adrenoreceptors (β-AR) located in the temporomandibular joint (TMJ) of rats suppresses formalin-induced TMJ nociceptive behaviour in both male and female rats, but female rats are more responsive. In this study, we investigated whether gonadal hormones modulate the responsiveness to local β-blocker-induced antinociception in the TMJ of rats. Co-administration of each of the selective β1 (atenolol), β2 (ICI 118.551) and β3 (SR59230A)-AR antagonists with equi-nociceptive concentrations of formalin in the TMJ of intact, gonadectomized and hormone-treated gonadectomized male and female rats. Atenolol, ICI 118.551 and SR59230A significantly reduced formalin-induced TMJ nociception in a dose response fashion in all groups tested. However, a lower dose of each β-AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact and testosterone-treated gonadectomized male rats. In the female groups, a lower dose of β1 -AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact or gonadectomized rats treated with progesterone or a high dose of oestradiol; a lower dose of β2 -AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact and gonadectomized rats treated with low or high dose of oestradiol. Gonadal hormones may reduce the responsiveness to local β-blocker-induced antinociception in the TMJ of male and female rats. However, their effect depends upon their plasma level, the subtype of β-AR and the dose of β-blockers used.

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Quantifying global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the global scale, syntheses of the (15)N:(14)N ratio of soil organic matter across climate gradients provide key insights into understanding global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in (15)N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8°C, soil δ(15)N was invariant with MAT. At the global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil δ(15)N showed no consistent trends across global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and global budgets of gaseous N loss.

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In our previous study, we have found that 5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridine-3-yl]-pyrimidin-4-ylamine (BAY 41-2272), a guanylate cyclase agonist, activates human monocytes and the THP-1 cell line to produce the superoxide anion, increasing in vitro microbicidal activity, suggesting that this drug can be used to modulate immune functioning in primary immunodeficiency patients. In the present work, we investigated the potential of the in vivo administration of BAY 41-2272 for the treatment of Candida albicans and Staphylococcus aureus infections introduced via intraperitoneal and subcutaneous inoculation. We found that intraperitoneal treatment with BAY 41-2272 markedly increased macrophage-dependent cell influx to the peritoneum in addition to macrophage functions, such as spreading, zymosan particle phagocytosis and nitric oxide and phorbol myristate acetate-stimulated hydrogen peroxide production. Treatment with BAY 41-2272 was highly effective in reducing the death rate due to intraperitoneal inoculation of C. albicans, but not S. aureus. However, we found that in vitro stimulation of peritoneal macrophages with BAY 41-2272 markedly increased microbicidal activities against both pathogens. Our results show that the prevention of death by the treatment of C. albicans-infected mice with BAY 41-2272 might occur primarily by the modulation of the host immune response through macrophage activation.

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In this work, the volatile chromatographic profiles of roasted Arabica coffees, previously analyzed for their sensorial attributes, were explored by principal component analysis. The volatile extraction technique used was the solid phase microextraction. The correlation optimized warping algorithm was used to align the gas chromatographic profiles. Fifty four compounds were found to be related to the sensorial attributes investigated. The volatiles pyrrole, 1-methyl-pyrrole, cyclopentanone, dihydro-2-methyl-3-furanone, furfural, 2-ethyl-5-methyl-pyrazine, 2-etenyl-n-methyl-pyrazine, 5-methyl-2-propionyl-furan compounds were important for the differentiation of coffee beverage according to the flavour, cleanliness and overall quality. Two figures of merit, sensitivity and specificity (or selectivity), were used to interpret the sensory attributes studied.

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas. Faculdade de Educação Física