947 resultados para Barefoot Running
Resumo:
OBJETIVO: Sintetizar e analisar as evidências da literatura sobre a associação entre atividade física e qualidade de vida. MÉTODOS: Revisão sistemática nas bases PubMed, Lilacs e SciELO com utilização dos descritores "physical activity", "motor activity", "exercise", "walking", "running", "physical fitness", "sport", "life style", "quality of life", "WHOQOL" e "SF". Foram selecionados 38 estudos publicados entre 1980 e 2010 que utilizaram algum instrumento de medida da atividade física e com alguma versão dos questionários Medical Outcomes Study 36-Item Short-Form Health Survey ou World Health Organization Quality of Life para avaliar a qualidade de vida. RESULTADOS: A maioria dos estudos apresentou delineamento transversal (68%), 18% foram experimentais, 8% de acompanhamento prospectivo (coorte) e 5% com delineamento misto (transversal e longitudinal). O questionário mais utilizado para avaliar a qualidade de vida foi o SF-36 (71%) e a atividade física foi auto-reportada em 82% dos estudos. Maior nível de atividade física associou-se à melhor percepção de qualidade de vida em idosos, adultos aparentemente saudáveis ou em diferentes condições de saúde. CONCLUSÕES: A associação entre atividade física e qualidade de vida é positiva e varia de acordo com o domínio analisado.
Resumo:
Projeto para obtenção do grau de Mestre em Engenharia Informática e de Computadores
Resumo:
The marriage of emerging information technologies with control technologies is a major driving force that, in the context of the factory-floor, is creating an enormous eagerness for extending the capabilities of currently available fieldbus networks to cover functionalities not considered up to a recent past. Providing wireless capabilities to such type of communication networks is a big share of that effort. The RFieldbus European project is just one example, where PROFIBUS was provided with suitable extensions for implementing hybrid wired/wireless communication systems. In RFieldbus, interoperability between wired and wireless components is achieved by the use specific intermediate networking systems operating as repeaters, thus creating a single logical ring (SLR) network. The main advantage of the SLR approach is that the effort for protocol extensions is not significant. However, a multiple logical ring (MLR) approach provides traffic and error isolation between different network segments. This concept was introduced in, where an approach for a bridge-based architecture was briefly outlined. This paper will focus on the details of the inter-Domain Protocol (IDP), which is responsible for handling transactions between different network domains (wired or wireless) running the PROFIBUS protocol.
Resumo:
A preliminary version of this paper appeared in Proceedings of the 31st IEEE Real-Time Systems Symposium, 2010, pp. 239–248.
Resumo:
Fieldbus communication networks aim to interconnect sensors, actuators and controllers within distributed computer-controlled systems. Therefore they constitute the foundation upon which real-time applications are to be implemented. A potential leap towards the use of fieldbus in such time-critical applications lies in the evaluation of its temporal behaviour. In the past few years several research works have been performed on a number of fieldbuses. However, these have mostly focused on the message passing mechanisms, without taking into account the communicating application tasks running in those distributed systems. The main contribution of this paper is to provide an approach for engineering real-time fieldbus systems where the schedulability analysis of the distributed system integrates both the characteristics of the application tasks and the characteristics of the message transactions performed by these tasks. In particular, we address the case of system where the Process-Pascal multitasking language is used to develop P-NET based distributed applications
Resumo:
Algarve Province, Southern Portugal, corresponds in part to a meso-cenozoic basin running along the coast from Cabo S. Vicente to beyond Spanish border. Structurally it is a big monocline plunging southwards much deformed mainly by two East-West longitudinal flexures. Lithostratigraphical and chronostratigraphical studies dealt specially with Jurassic formations. This and the geological mapping of the post-Hercynian sedimentary formations allow us to define the following units: Triassic-Lower Liassic Arenitos de Silves (Silves sandstones sensu P. Choffat, pro parte) - At their base the Silves sandstones (0-150m) are represented mainly by cross-bedded red sandstones. This unit is Upper Triassic (Keuper) in age, on the evidence of some Brachiopoda. Complexo margo-carbonatado de Silves (Silves marl-limestone complex=Silves sandstones sensu P. Choffat, pro parte) (80-200m) overlies the preceding, it may be reported to the Upper Triassic-Hettangian. It consists of a thick pelite-marl-dolomite-limestone series with many intercalations of greenstones. Since no fossils were found it is not possible to conclude whether it is still Hettangian or if it does correspond, in the whole or in part, already to the Sinemurian. Liassic Dolomitos e calcários dolomíticos de Espiche (Espiche dolomite-rocks and dolomitic-limestones) - The usually massive and finely crystalline or saccharoidal dolomites and dolomitic-limestones are the toughest strata of the Algarve margin giving rise to several hills. Its thickness attains in certain points 60 metres at least. Based on geometry and on lithological similarities with the carbonated complex of the northern basin of Tagus river (Peniche, São Pedro de Muel, Quiaios), this formation can be accepted as Sinemurian in age. As it happens with the carbonated complex, here also the first dolomite beds are non-isochronal throughout the region; upper time-limit of the dolomitic facies is either Lower Carixian, Lower Toarcian or even Lower Dogger. The dolomitization is secondary but not much later than sedimentation. However, between Cabo S. Vicente-Vila do Bispo there is evidence of an even later secondary dolomitization related to the regional fault complex. Calcário dolomítico com nódulos de silex da praia de Belixe (Belixe beach dolomitic-limestone with silex nodules) (50-55m) - Ascribed to Lower or Middle Carixian on the basis of Platypleuroceras sp., Metaderoceras sp. nov. and M. gr. Venarense. Calcário cristalino compacto com Protogrammoceras, Fuciniceras e ? Argutarpites de Belixe (Belixe compact crystalline limestone with Protogrammoceras, Fuciniceras and ? Argutarpites) (30m) - Ascribed to Lower Domerian. Middle and Upper Domerian are indicated but by a single specimen of ? Argutarpites. Calcários margosos e margas com Dactylioceras semicelatum e Harpoceratídeos de Armação Nova (Armação Nova marly limestones and marls with D. semicelatum and Harpoceratidae) (25m) -Ascribed to Lower Toarcian. Middle and Upper Toarcian formations are not known in the Algarve. Dogger Calcários oolíticos, c. corálicos, c. pisolíticos, c. calciclásticos, c. dolomíticos e dolomitos de Almadena (Almadena oolitic-limestones, coral-reef-limestones, pisolite-limestones, limeclastic-limestones, dolomitic-limestones and dolomite-rocks) (more than 50 metres), with lagoonal facies. Ascribed to Aalenian-Bathonian-? Callovian. Margas acinzentadas e calcários detríticos com Zoophycos da praia de Mareta (Mareta beach greyish marls and detritical limestones with Zoophycos) (40m) - Pelagic transreef facies with Upper Bajocian and Bathonian ammonites. Calcários margosos e margas da praia de Mareta (Mareta beach pelagic marly-limestones and marls) (110m) - Ascribed to the Callovian on its ammonites. Malm Near Cabo S. Vicente and Sagres the first Upper Jurassic level consists of a yellowish-brown nodular, compact, locally phosphated and ferruginous, sometimes conglomeratic, marly limestone (0,35-1,50m) containing a rich macrofauna, which includes: 1) Callovian forms unknown at Lower Oxfordian; 2) Upper Callovian forms that still survived in Lower and Middle Oxfordian; 3) Lower Oxfordian forms (Mariae and Cordatum Zones); 4) Lower and Middle Oxfordian forms (Mariae to Plicatilis Zone); 5) Middle Oxfordian forms (plicatilis Zone), and some ones appearing in Middle Oxfordian. This condensed deposit is therefore dated from Middle Oxfordian (Plicatilis Zone). The other Upper Jurassic lithostratigraphical units were also mapped but their detailed study is not presented in this work. Correlations between lithostratigraphical and chronostratigraphical scales from P. Choffat, J. Pratsch, C. Palain and from the author are stated. Further correlations are attempted between zonc scales of Carixian-Lower Toarcian and Upper Bajocian-Middle Oxfordian of France, Spain (Asturias, Iberian and Betic Chains), Argel (Orania) and Portugal (northern Tagus basin and Algarve). The study of pyritous fossil assemblages common in Upper Bathonian-Lower Callovian marly levels of the praia da Mareta seems to suggest that these sediments were deposited in a bay or in an almost closed coastal re-entrance virtually without deep water circulation. Although such conditions may occur at any depth one may suppose that these ones actually correspond to an infralittoral neritic environment. The thaphocoenosis collected there are almost entirely composed of nektonic (ammonites, Belemnites) and planktonic (Bositra) faunas. The sedentary (crinoids, brachiopods) or free (sea-urchins, gastropods) epibenthonic forms are very scarce; endobenthonic forms are not known. The palaeontological study of all Nautiloids and Ammonoids of the Liassic and Dogger is presented (except Kosmoceratidae and Perisphinctaceae). Among the thirty one taxa dealt with, one is new (Metaderoceras sp. nov.) and the great majority of the others has been identified for the first time in Algarve. Some others have never been reported before in Portuguese formations. The evolution, during Jurassic times, of the sedimentary basins of the Portuguese plate margin is described. The absence of Cephalopods in the very extensive marly and dolomitic limestones, partly marine, suggests that, during Lower Liassic, palaeogeography underwent no great changes. Dolomitic-limestone with silex nodules from Cabo S. Vicente contain the first ammonites recorded at the base of the Middle Liassic. This facies, although very common in Tethys, is unknown north of the Tagus. The faunal assemblage has a mediterranean to submediterranean character. Comparisons between faunal assemblage" from Algarve with the ones known north of the Tagus show that communications between Boreal Europe and Tethys, virtually non-existent during Lower and Middle Carixian, became very easy during Lower Domerian. In earlier Pliensbachian times two distinct seas were adjacent to the Iberian plate. One, an epicontinental sea with a tethyan fauna, extended southwards from the Meseta margin. Another, was a boreal sea; during its transgressive episodes boreal faunas attained into the basin north of the Tagus. During Middle Carixian and Lower Domerian, owing to simultaneous transgressions, these two seas joined together allowing faunal exchanges along the epicontinental areas which limited the emerging hercynian chains belts. During Liassic, the Algarve belonged undoubtedly to the tethyan submediterranean province. The area north of the Tagus, on the contrary, was a complex realm where subboreal and tethyan affinities alternatively prevailed. In the Algarve the first Middle Jurassic deposits do frequently show lateral thickness reductions as well as unconformities contemporaneous with other generalized disturbances on the sedimentation processes in other parts of Europe. By this time, near Sagres, a barrier reef developed separating lagoonal or ante-reef facies from the transreef pelagic zone. The presence of tethyan fauna, the abundance of Phylloceratidae and the absence of boreal forms allow us to consider the Algarve basin as a submediterranean province. The presence of Callovian pelagic fossiliferous formations in the Loulé area shows that during Middle Jurassic the marl-limestone transreef sedimentation was not confined to the western Algarve. They would extend eastwards where they only can be seen in the core of some anticlines. This is due to the progressive sinking of the meso-cenozoic formations as we proceed towards the South of the Sagres-Algoz-Querença flexure. In the whole of the Peninsule, and as for the Middle Callovian, an important regression can be clearly recognized on the evidence of an erosion surface which strikes obliquely the Middle and Upper Callovian strata. The geographic boundaries of the different faunal provinces are not changed by the presence of many Kosmoceratidae in the phosphate nodules since they are but a minority in comparison with the tethyan forms. An abstract model can be constructed showing that in Western Europe the Kosmoceratidae may have migrated South and westwards through a channel of the sea that linked Paris basin to Poitou and Aquitaine. By migrating between the Iberian meseta and the Armorican massif this fauna reached northern Tagus basin at the beginning of Upper Callovian (Athleta Zone); this south and southwest bound migration would have proceeded, allowing such forms to reach Algarve basin only in latest Callovian times (Lamberti Zone). This migration means that during Middle Jurassic a widely spread North Atlantic sea would exist, flooding the western part of Portugal up to the Poitou.
Resumo:
This paper reports some research work that has been done to support Geological Survey's field work for the 1:50.000 Carta Geológica de Portugal, (sheets 19-C Figueira da Foz and 19-D Coimbra-Lousã). Its main purpose was to establish the age of some continental formations. At Cerâmica do Mondego, Ld.ª near Taveiro, two series were observed. The lower one is mainly pelitic, montmorillonite being predominant. It also includes some sandy beds and channel deposits with high energy sediments (conglomerate with limestone pebbles). The upper series lies unconformably upon the former, and there is a neat discontinuity surface between the two. It mainly consists of sands, kaolinite being the most abundant of the clay minerals. This seems to indicate an intensive weathering, an acid, well drained environment and transportation by quite high energy running waters. No fossils were recorded. Preliminary paleontological results are presented, along with some data concerning other localities (Aveiro, etc.). Fossils found in the lower series are: gastropoda (Bulimus gaudryi, TV. 15 bed), several vertebrates (TV. 18), fishes (TV. 19?) and plants (TV. 19-TV. 24). Vertebrata belong to the same fauna as that from Vizo, Aveiro, etc. The presence of mammals is most important as only a single tooth was previously Know in Europe (Southern France) in Late Cretaceous formations. Elsewhere there are some mammalian remains in Peru besides the rich assemblages found in the USA and Mongolia. Plants are representative of the «Debeya flora» well known at several localities in Beira Litoral province, in «Buçaco sandstones», and in Lisbon's «Basaltic Complex». The most important stratigraphical conclusion is that the lower series is Upper Campanian and/or Maastrichtian in age, and not Tertiary as sometimes it has been considered. As at Aveiro, «Bebeya flora» occurs in-beds somewhat higher than those with the Aveiro-Vizo-Taveiro vertebrate fauna. Correlation with other «Debeya flora» localities are now more clear. Data concerning Taveiro lower series, in the whole, point out to a rather warm (and moist?) environment in an occasionally (seasonally?) flooded region.
Resumo:
This paper reports some research work that has been done to support Geological Survey's field work for the 1:50.000 Carta Geológica de Portugal, (sheets 19-C Figueira da Foz and 19-D Coimbra-Lousã). Its main purpose was to establish the age of some continental formations. At Cerâmica do Mondego, Lda. near Taveiro, two series were observed. The lower one is mainly pelitic, montmorillonite being predominant. It also includes some sandy beds and channel deposits with high energy sediments (conglomerate with limestone pebbles). The upper series lies unconformably upon the former, and there is a neat discontinuity surface between the two. It mainly consists of sands, kaolinite being the most abundant of the clay minerals. This seems to indicate an intensive weathering, an acid, well drained environment and transportation by quite high energy running waters. No fossils were recorded. Preliminary paleontological results are presented, along with some data concerning other localities (Aveiro, etc). Fossils found in the lower series are: gastropoda (Bulimus gaudryi, TV. 15 bed), several vertebrates (TV. 18), fishes (TV. 19?) and plants (TV. 19-TV. 24). Vertebrata belong to the same fauna as that from Vizo, Aveiro, etc. The presence of mammals is most important as only a single tooth was previously know in Europe (Southern France) in Late Cretaceous formations. Elsewhere there are some mammalian remains in Peru besides the rich assemblages found in the USA and Mongolia. Plants are representative of the «Debeya flora» well known at several localities in Beira Litoral province, in «Buçaco sandstones», and in Lisbon's «Basaltic Complex». The most important stratigraphical conclusion is that the lower series is Upper Campanian and/or Maastrichtian in age, and not Tertiary as sometimes it has been considered. As at Aveiro, «Bebeya flora» occurs in-beds somewhat higher than those with the Aveiro-Vizo-Taveiro vertebrate fauna. Correlation with other «Debeya flora» localities are now more clear. Data concerning Taveiro lower series, in the whole, point out to a rather warm (and moist?) environment in an occasionally (seasonally?) flooded region.
Resumo:
Consider the problem of scheduling a set of sporadic tasks on a multiprocessor system to meet deadlines using a task-splitting scheduling algorithm. Task-splitting (also called semi-partitioning) scheduling algorithms assign most tasks to just one processor but a few tasks are assigned to two or more processors, and they are dispatched in a way that ensures that a task never executes on two or more processors simultaneously. A particular type of task-splitting algorithms, called slot-based task-splitting dispatching, is of particular interest because of its ability to schedule tasks with high processor utilizations. Unfortunately, no slot-based task-splitting algorithm has been implemented in a real operating system so far. In this paper we discuss and propose some modifications to the slot-based task-splitting algorithm driven by implementation concerns, and we report the first implementation of this family of algorithms in a real operating system running Linux kernel version 2.6.34. We have also conducted an extensive range of experiments on a 4-core multicore desktop PC running task-sets with utilizations of up to 88%. The results show that the behavior of our implementation is in line with the theoretical framework behind it.
Resumo:
Modeling the fundamental performance limits of Wireless Sensor Networks (WSNs) is of paramount importance to understand their behavior under the worst-case conditions and to make the appropriate design choices. This is particular relevant for time-sensitive WSN applications, where the timing behavior of the network protocols (message transmission must respect deadlines) impacts on the correct operation of these applications. In that direction this paper contributes with a methodology based on Network Calculus, which enables quick and efficient worst-case dimensioning of static or even dynamically changing cluster-tree WSNs where the data sink can either be static or mobile. We propose closed-form recurrent expressions for computing the worst-case end-to-end delays, buffering and bandwidth requirements across any source-destination path in a cluster-tree WSN. We show how to apply our methodology to the case of IEEE 802.15.4/ZigBee cluster-tree WSNs. Finally, we demonstrate the validity and analyze the accuracy of our methodology through a comprehensive experimental study using commercially available technology, namely TelosB motes running TinyOS.
Resumo:
Modeling the fundamental performance limits of Wireless Sensor Networks (WSNs) is of paramount importance to understand their behavior under worst-case conditions and to make the appropriate design choices. In that direction this paper contributes with an analytical methodology for modeling cluster-tree WSNs where the data sink can either be static or mobile. We assess the validity and pessimism of analytical model by comparing the worst-case results with the values measured through an experimental test-bed based on Commercial-Off- The-Shelf (COTS) technologies, namely TelosB motes running TinyOS.
Resumo:
Portugal had only very few foresight exercises on the automobile sector, and the most recent one was a survey held in a project on work organisation systems in the automobile industry, its recent historical paths and the special strategies of location of companies (the WorTiS project). This involved several teams with different disciplinary backgrounds and from two Portuguese universities. The provisional main results of the first round of a Delphi survey held in Portugal on the automotive sector were already published, but a further analysis was not yet done. This foresight survey was done under the WorTiS project, developed in 2004 by IET – Research Centre on Enterprise and Work Innovation (at FCT-UNL), and financed by the Portuguese Ministry of Science and Technology. Some of this experience on foresight analysis is also been transferred to other projects, namely the WORKS project on work organisation restructuring in the knowledge society that received the support from EC and still is running. The majority of experts considered having an average of less knowledge in almost all the scenario topics presented. This means that information on the automotive industry is not spread enough among academics or experts in related fields (regional scientists, innovation economists, engineers, sociologists). Some have a good knowledge but in very specialised fields. Others have expertise on foresight, or macroeconomics, or management sciences, but feel insecure on issues related with futures of automobile sector. Nevertheless, we considered specially the topics where the experts considered themselves to have some knowledge. There were no “irrelevant” topics considered as such by the expert panel. There are also no topics that are not considered a need for co-operation. The lack of technological infrastructures was not considered as a hindered factor for the accomplishment of any scenario. The experts’ panel considered no other international competence besides US, Japan or Germany in these topics. Special focus will be made in this paper on the topic 2. Public policy and automobile industries, and more specifically on the technological and/or research policies issues, where one can specify the automobile’s role in transport policies with further implications like environment, safety, energy, mobility.
Resumo:
Constrained and unconstrained Nonlinear Optimization Problems often appear in many engineering areas. In some of these cases it is not possible to use derivative based optimization methods because the objective function is not known or it is too complex or the objective function is non-smooth. In these cases derivative based methods cannot be used and Direct Search Methods might be the most suitable optimization methods. An Application Programming Interface (API) including some of these methods was implemented using Java Technology. This API can be accessed either by applications running in the same computer where it is installed or, it can be remotely accessed through a LAN or the Internet, using webservices. From the engineering point of view, the information needed from the API is the solution for the provided problem. On the other hand, from the optimization methods researchers’ point of view, not only the solution for the problem is needed. Also additional information about the iterative process is useful, such as: the number of iterations; the value of the solution at each iteration; the stopping criteria, etc. In this paper are presented the features added to the API to allow users to access to the iterative process data.
Resumo:
In global scientific experiments with collaborative scenarios involving multinational teams there are big challenges related to data access, namely data movements are precluded to other regions or Clouds due to the constraints on latency costs, data privacy and data ownership. Furthermore, each site is processing local data sets using specialized algorithms and producing intermediate results that are helpful as inputs to applications running on remote sites. This paper shows how to model such collaborative scenarios as a scientific workflow implemented with AWARD (Autonomic Workflow Activities Reconfigurable and Dynamic), a decentralized framework offering a feasible solution to run the workflow activities on distributed data centers in different regions without the need of large data movements. The AWARD workflow activities are independently monitored and dynamically reconfigured and steering by different users, namely by hot-swapping the algorithms to enhance the computation results or by changing the workflow structure to support feedback dependencies where an activity receives feedback output from a successor activity. A real implementation of one practical scenario and its execution on multiple data centers of the Amazon Cloud is presented including experimental results with steering by multiple users.
Resumo:
In practice the robotic manipulators present some degree of unwanted vibrations. The advent of lightweight arm manipulators, mainly in the aerospace industry, where weight is an important issue, leads to the problem of intense vibrations. On the other hand, robots interacting with the environment often generate impacts that propagate through the mechanical structure and produce also vibrations. In order to analyze these phenomena a robot signal acquisition system was developed. The manipulator motion produces vibrations, either from the structural modes or from endeffector impacts. The instrumentation system acquires signals from several sensors that capture the joint positions, mass accelerations, forces and moments, and electrical currents in the motors. Afterwards, an analysis package, running off-line, reads the data recorded by the acquisition system and extracts the signal characteristics. Due to the multiplicity of sensors, the data obtained can be redundant because the same type of information may be seen by two or more sensors. Because of the price of the sensors, this aspect can be considered in order to reduce the cost of the system. On the other hand, the placement of the sensors is an important issue in order to obtain the suitable signals of the vibration phenomenon. Moreover, the study of these issues can help in the design optimization of the acquisition system. In this line of thought a sensor classification scheme is presented. Several authors have addressed the subject of the sensor classification scheme. White (White, 1987) presents a flexible and comprehensive categorizing scheme that is useful for describing and comparing sensors. The author organizes the sensors according to several aspects: measurands, technological aspects, detection means, conversion phenomena, sensor materials and fields of application. Michahelles and Schiele (Michahelles & Schiele, 2003) systematize the use of sensor technology. They identified several dimensions of sensing that represent the sensing goals for physical interaction. A conceptual framework is introduced that allows categorizing existing sensors and evaluates their utility in various applications. This framework not only guides application designers for choosing meaningful sensor subsets, but also can inspire new systems and leads to the evaluation of existing applications. Today’s technology offers a wide variety of sensors. In order to use all the data from the diversity of sensors a framework of integration is needed. Sensor fusion, fuzzy logic, and neural networks are often mentioned when dealing with problem of combing information from several sensors to get a more general picture of a given situation. The study of data fusion has been receiving considerable attention (Esteban et al., 2005; Luo & Kay, 1990). A survey of the state of the art in sensor fusion for robotics can be found in (Hackett & Shah, 1990). Henderson and Shilcrat (Henderson & Shilcrat, 1984) introduced the concept of logic sensor that defines an abstract specification of the sensors to integrate in a multisensor system. The recent developments of micro electro mechanical sensors (MEMS) with unwired communication capabilities allow a sensor network with interesting capacity. This technology was applied in several applications (Arampatzis & Manesis, 2005), including robotics. Cheekiralla and Engels (Cheekiralla & Engels, 2005) propose a classification of the unwired sensor networks according to its functionalities and properties. This paper presents a development of a sensor classification scheme based on the frequency spectrum of the signals and on a statistical metrics. Bearing these ideas in mind, this paper is organized as follows. Section 2 describes briefly the robotic system enhanced with the instrumentation setup. Section 3 presents the experimental results. Finally, section 4 draws the main conclusions and points out future work.