965 resultados para 091302 Automation and Control Engineering


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This paper presents the results of an investigation into the utility of remote sensing (RS) using meteorological satellites sensors and spatial interpolation (SI) of data from meteorological stations, for the prediction of spatial variation in monthly climate across continental Africa in 1990. Information from the Advanced Very High Resolution Radiometer (AVHRR) of the National Oceanic and Atmospheric Administration's (NOAA) polar-orbiting meteorological satellites was used to estimate land surface temperature (LST) and atmospheric moisture. Cold cloud duration (CCD) data derived from the High Resolution Radiometer (HRR) onboard the European Meteorological Satellite programme's (EUMETSAT) Meteosat satellite series were also used as a RS proxy measurement of rainfall. Temperature, atmospheric moisture and rainfall surfaces were independently derived from SI of measurements from the World Meteorological Organization (WMO) member stations of Africa. These meteorological station data were then used to test the accuracy of each methodology, so that the appropriateness of the two techniques for epidemiological research could be compared. SI was a more accurate predictor of temperature, whereas RS provided a better surrogate for rainfall; both were equally accurate at predicting atmospheric moisture. The implications of these results for mapping short and long-term climate change and hence their potential for the study anti control of disease vectors are considered. Taking into account logistic and analytical problems, there were no clear conclusions regarding the optimality of either technique, but there was considerable potential for synergy.

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Contested Open Spaces?: Access and control issues in Tundikhel, Kathmandu

Public spaces play a role of political, economic and cultural transformation of cities and the impact of these transformations on the nature of public space.

Urban open space(s) in Kathmandu have been an important part of the city’s urbanism. Historically they have played an important role in the city as spaces for religious, cultural, social and political and military activities during the 300 years of unified monarchy. Throughout the civil war period (Maoist insurgency between 1996 and 2006) they became material locations for political activities, and a site for protests and dharnas. In post-conflict Kathmandu, especially since the abolition of Monarchy in May 28, 2008, these spaces are increasingly seen being claimed by street hawkers, informal sellers and individuals reflecting a new set of users and functions, whereas a significant part of Tundikhel still remains under the military occupation posing important questions around access, identity and control of an important space.


Public spaces are broadly defined as crossroads where different paths and trajectories meet, sometimes overlapping and other times colliding (Madanipour, 2003). Using Tudikhel in Kathmandu, this research examines the increasing collision and contestations witnessed through social, political and neoliberal interactions. It explores how spaces are constantly
contested, negotiated and as a result reshaped through these interactions. It is observed that multiple forces are at play to gain control and access of this important open space, leading to increasing fragmentation of the space, and erosion of its historic significance both as cultural venue and a symbol of democracy in modern Nepal. It is argued that increasing disconnection of Tudikhel from wider urban setting has contributed to exacerbation of these contestations

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High-affinity nitrate transport was examined in intact hyphae of Neurospora crassa using electrophysiological recordings to characterize the response of the plasma membrane to NO3 - challenge and to quantify transport activity. The NO3 --associated membrane current was determined using a three electrode voltage clamp to bring membrane voltage under experimental control and to compensate for current dissipation along the longitudinal cell axis. Nitrate transport was evident in hyphae transferred to NO3 --free, N-limited medium for 15 hr, and in hyphae grown in the absence of a nitrogen source after a single 2-min exposure to 100 μM NO3 -. In the latter, induction showed a latency of 40-80 min and rose in scalar fashion with full transport activity mensurable approx. 100 min after first exposure to NO3 -; it was marked by the appearance of a pronounced sensitivity of membrane voltage to extracellular NO3 - additions which, after induction, resulted in reversible membrane depolarizations of (+)54-85 mV in the presence of 50 μM NO3 -; and it was suppressed when NH4 +, was present during the first, inductive exposure to NO3 -. Voltage clamp measurements carried out immediately before and following NO3 - additions showed that the NO3 --evoked depolarizations were the consequence of an inward-directed current that appeared in parallel with the depolarizations across the entire range of accessible voltages -400 to +100 mV). Measurements of NO3 - uptake using NO3 --selective macroelectrodes indicated a charge stoichiometry for NO3 - transport of 1(+):1(NO3 -) with common K(m) and J(max) values around 25 μM and 75 pmol NO3 - cm-2sec-1, respectively, and combined measurements of pH(o) and [NO3 -](o) showed a net uptake of approx. 1 H+ with each NO3 - anion. Analysis of the NO3 - current demonstrated a pronounced voltage sensitivity within the normal physiological range between -300 and -100 mV as well as interactions between the kinetic parameters of membrane voltage, pH(o) and [NO3 -](o). Increasing the bathing pH from 5.5 to 8.0 reduced the current and the associated membrane depolarizations 2- to 4-fold. At a constant pH(o) of 6.1, driving the membrane voltage from -350 to -150 mV resulted in an approx. 3-fold reduction in the maximum current and a 5-fold rise in the apparent affinity for NO3 -. By contrast, the same depolarization effected an approx. 20% fall in the K(m) for transport as a function in [H+](o). These, and additional results are consistent with a charge-coupling stoichiometry of 2(H+) per NO anion transported across the membrane, and implicate a carrier cycle in which NO binding is kinetically adjacent to the rate-limiting step of membrane charge transit. The data concur with previous studies demonstrating a pronounced voltage-dependence to high-affinity NO3 - transport system in Arabidopsis, and underline the importance of voltage as a kinetic factor controlling NO3 - transport; finally, they distinguish metabolite repression of NO3 - transport induction from its sensitivity to metabolic blockade and competition with the uptake of other substrates that draw on membrane voltage as a kinetic substrate.

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This paper reports on a research project designed to discover what schools are teaching in Religious Education in Northern Ireland and what procedures are in place to maintain standards in the delivery of the subject. A search through literature shows that little research has been carried out to determine what is being taught in Religious Education in Northern Ireland. It also indicates that there are very weak systems of control to measure the effectiveness or quality of what is delivered. A survey of the websites of all Post-Primary schools in the region was used to provide some answers to the basic question of what is being taught in RE. Using content and discourse analysis of these alongside supporting documentary sources (textbooks and exam specifications), it is possible to get a clearer picture of how the Northern Ireland Core Syllabus for Religious Education and any additional curricular elements are delivered in schools. The findings show that a significant minority of schools do not publicly articulate what pupils do in religious education. In situations where the content of religious education is made clear, some definite trends are evident. Despite the existence of a statutory core syllabus, there is significant variation in what is taught in schools. The content is most divergent from the syllabus in relation to the teaching of World Religions at Key Stage 3 and at Key Stage 4 whole elements of the syllabus are neglected due to limited conformity between the syllabus and exam specifications. These results raise important questions about the systems of regulation and control of the subject in the region. In law the subject is exempt from formal inspection by the local inspection authority; instead, a form of inspection is allowed for by the Christian churches who design the syllabus, but it is a process that is either entirely neglected or entirely unreported in situations where it does occur. It is argued that these findings raise questions of more general concern for this and other regions in Europe where the teaching of religious education is largely unregulated. For example, to what extent should states take an interest in what is taught in religious education, how it is delivered, what values it promotes and how standards of teaching and learning in the subject are upheld?

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This is an analysis of the case law of the European Court of Human Rights on the obligation on States to plan and control the use of potentially lethal force by their police and military personnel. It illustrates the Court's attachment to the strict or careful scrutiny test and suggests how the Court might want to develop its jurisprudence in the future.

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The fast increase in the energy’s price has brought a growing concern about the highly expensive task of transporting water. By creating an hydraulic model of the Water Supply System’s (WSS) network and predicting its behaviour, it is possible to take advantage of the energy’s tariffs, reducing the total cost on pumping activities. This thesis was developed, in association with a technology transfer project called the E-Pumping. It focuses on finding a flexible supervision and control strategy, adaptable to any existent Water Supply System (WSS), as well as forecasting the water demand on a time period chosen by the end user, so that the pumping actions could be planned to an optimum schedule, that minimizes the total operational cost. The OPC protocol, associated to a MySQL database were used to develop a flexible tool of supervision and control, due to their adaptability to function with equipments from various manufacturers, being another integrated modular part of the E-Pumping project. Furthermore, in this thesis, through the study and performance tests of several statistical models based on time series, specifically applied to this problem, a forecasting tool adaptable to any station, and whose model parameters are automatically refreshed at runtime, was developed and added to the project as another module. Both the aforementioned modules were later integrated with an Graphical User Interface (GUI) and installed in a pilot application at the ADDP’s network. The implementation of this software on WSSs across the country will reduce the water supply companies’ running costs, improving their market competition and, ultimately, lowering the water price to the end costumer.

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The aim of this chapter is to introduce background concepts in nonlinear systems identification and control with artificial neural networks. As this chapter is just an overview, with a limited page space, only the basic ideas will be explained here. The reader is encouraged, for a more detailed explanation of a specific topic of interest, to consult the references given throughout the text. Additionally, as general books in the field of neural networks, the books by Haykin [1] and Principe et al. [2] are suggested. Regarding nonlinear systems identification, covering both classical and neural and neuro-fuzzy methodologies, Reference 3 is recommended. References 4 and 5 should be used in the context of B-spline networks.

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Tese de doutoramento, Física, Universidade de Lisboa, Faculdade de Ciências, 2014

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Tese de doutoramento, Farmácia (Microbiologia), Universidade de Lisboa, Faculdade de Farmácia, 2015

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The main objective of this text is to warn against atmospherics. However comfortable it might appear, an atmosphere is politically suspicious because it numbs a body into an affective embrace of stability and permanence. It becomes doubly suspicious because a body desires to be part of the atmosphere. For this reason, I rethink both affect and atmosphere ontologically rather than phenomenologically. I argue that an atmosphere is engineered by subsuming individual affects to what I call, following Sloterdijk, an atmospheric glasshouse. I suggest that this happens in four steps: a distinction between inside and outside through partitioning; inclusion of the outside inside; illusion of synthesis; and dissimulation. In order to do this, I begin with air as the elemental paradox of ontological continuum and rupture. I carry on with the passage from air to atmosphere while retaining the discourse around continuum and rupture. Finally, I indicate a way of rupturing the atmospheric continuum through the ontological movement of withdrawal from the atmosphere. The ultimate goal of the article is to sketch a problematic of atmospherics that puts together without synthesising an elemental ontology of continuum and rupture.

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The main objective of this text is to warn against atmospherics. However comfortable it might appear, an atmosphere is politically suspicious because it numbs a body into an affective embrace of stability and permanence. It becomes doubly suspicious because a body desires to be part of the atmosphere. For this reason, I rethink both affect and atmosphere ontologically rather than phenomenologically. I argue that an atmosphere is engineered by subsuming individual affects to what I call, following Sloterdijk, an atmospheric glasshouse. I suggest that this happens in four steps: a distinction between inside and outside through partitioning; inclusion of the outside inside; illusion of synthesis; and dissimulation. In order to do this, I begin with air as the elemental paradox of ontological continuum and rupture. I carry on with the passage from air to atmosphere while retaining the discourse around continuum and rupture. Finally, I indicate a way of rupturing the atmospheric continuum through the ontological movement of withdrawal from the atmosphere. The ultimate goal of the article is to sketch a problematic of atmospherics that puts together without synthesising an elemental ontology of continuum and rupture.

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Power converters play a vital role in the integration of wind power into the electrical grid. Variable-speed wind turbine generator systems have a considerable interest of application for grid connection at constant frequency. In this paper, comprehensive simulation studies are carried out with three power converter topologies: matrix, two-level and multilevel. A fractional-order control strategy is studied for the variable-speed operation of wind turbine generator systems. The studies are in order to compare power converter topologies and control strategies. The studies reveal that the multilevel converter and the proposed fractional-order control strategy enable an improvement in the power quality, in comparison with the other power converters using a classical integer-order control strategy. (C) 2010 Elsevier Ltd. All rights reserved.