785 resultados para on line learning
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The Proportional Integral and Devirative (PID) controller autotuning is an important problem, both in practical and theoretical terms. The autotuning procedure must take place in real-time, and therefore the corresponding optimisation procedure must also be executed in real-time and without disturbing on-line control.
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The aim of the present study is to understand the effects of international expansion on firms’ acquisition of marketing learning. This study’s focus on marketing learning complements previous research on the impact of internationalization on the development of foreign-market and technological knowledge. The research finds that the scope of a firm’s international activities, perception of gaps in marketing knowledge, and external social capital positively influence firms’ acquisition of marketing learning. However, firm’s age at initial international market entry appears not to be a significant factor. The study adds to the very limited body of research on the marketing learning outcomes of international expansion, while also offering rare empirical insights from the Middle East on this important subject matter. The paper discusses implications for international managers, policy makers, and future researchers.
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To boost logic density and reduce per unit power consumption SRAM-based FPGAs manufacturers adopted nanometric technologies. However, this technology is highly vulnerable to radiation-induced faults, which affect values stored in memory cells, and to manufacturing imperfections. Fault tolerant implementations, based on Triple Modular Redundancy (TMR) infrastructures, help to keep the correct operation of the circuit. However, TMR is not sufficient to guarantee the safe operation of a circuit. Other issues like module placement, the effects of multi- bit upsets (MBU) or fault accumulation, have also to be addressed. In case of a fault occurrence the correct operation of the affected module must be restored and/or the current state of the circuit coherently re-established. A solution that enables the autonomous restoration of the functional definition of the affected module, avoiding fault accumulation, re-establishing the correct circuit state in real-time, while keeping the normal operation of the circuit, is presented in this paper.
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The confluence of education with the evolution of technology boosted the paradigm shift of the face-to-face learning to distance learning. In this scenario e-Learning plays an essential role as a facilitator of the teaching/learning process. However new demands associated with the new Web paradigm require that existent e-Learning environments characterized mostly by monolithic systems begin interacting with new specialized services. In this decentralized scenario the definition of a strategy of interoperability is the cornerstone to ensure the standardization communication among systems. This paper presents a definition of an interoperability strategy for an e-Learning environment at our School (ESEIG) called PEACE – Project for ESEIG Academic Content Environment. This new interoperability model relies on the application of several coordination and integration standards on several services, controlled by teachers and students, and included in the PEACE environment such as social networks, repositories, libraries, e-portfolios, intelligent tutors, recommendation systems and virtual classrooms.
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Dissertation to obtain the degree of Master in Electrical and Computer Engineering
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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Gestão de Informação
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Os Sistemas de Informação Geográfica detêm um papel de crescente importância para a tomada de decisão ao nível do ordenamento do território, conforme o que a própria legislação evidencia. Existe uma carência de uniformização da informação para que possa existir um cruzamento eficiente e uma disponibilização mais facilitada à população e às diversas entidades. As instituições públicas, como é o caso do Instituto de Conservação e Florestas (ICNF I.P.), reconhecem esta necessidade, pelo que se propôs uma série de tarefas, para a concretização deste estágio, no sentido de a colmatar. Este instituto detém um papel de especial relevo na conservação do património natural assim como no ordenamento das áreas protegidas para que se possa usufruir das mesmas, sob um ponto de vista cada vez mais ecológico e promotor de desenvolvimento sustentável. A elaboração de um instrumento de gestão territorial, como se pode classificar a Carta de Desporto de Natureza (CDN), acarreta grande responsabilidade e exige um forte empenho, não apenas no envolvimento da população e das entidades que dele fruirão, mas no cumprimento da legislação existente quer para as atividades quer para o próprio território, no sentido da sua proteção, preservação e promoção de usos adequados. Neste trabalho procurou-se cumprir todas estas disposições sempre com o objetivo de, ao se construir normas de uniformização e ao se elaborar um exemplo de CDN para um território com tanto valor como é a Reserva Natural do Estuário do Tejo, tornar acessível a informação sobre esta área protegida. A intensão é também promover a motivação para a prática de um desporto natureza, saudável e em equilíbrio com o ambiente. O desafio não se ficou por aqui, havendo também a procura de utilização de Free Open Source Software, para que o processo de utilização e disponibilização informação SIG seja cada vez mais acessível e direta.
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The aim of the present study was to assess the influence of local environmental olfactory cues on place learning in rats. We developed a new experimental design allowing the comparison of the use of local olfactory and visual cues in spatial and discrimination learning. We compared the effect of both types of cues on the discrimination of a single food source in an open-field arena. The goal was either in a fixed or in a variable location, and could be indicated by local olfactory and/or visual cues. The local cues enhanced the discrimination of the goal dish, whether it was in a fixed or in a variable location. However, we did not observe any overshadowing of the spatial information by the local olfactory or visual cue. Rats relied primarily on distant visuospatial information to locate the goal, neglecting local information when it was in conflict with the spatial information.
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In distributed energy production, permanent magnet synchronous generators (PMSG) are often connected to the grid via frequency converters, such as voltage source line converters. The price of the converter may constitute a large part of the costs of a generating set. Some of the permanent magnet synchronous generators with converters and traditional separately excited synchronous generators couldbe replaced by direct-on-line (DOL) non-controlled PMSGs. Small directly networkconnected generators are likely to have large markets in the area of distributed electric energy generation. Typical prime movers could be windmills, watermills and internal combustion engines. DOL PMSGs could also be applied in island networks, such as ships and oil platforms. Also various back-up power generating systems could be carried out with DOL PMSGs. The benefits would be a lower priceof the generating set and the robustness and easy use of the system. The performance of DOL PMSGs is analyzed. The electricity distribution companies have regulations that constrain the design of the generators being connected to the grid. The general guidelines and recommendations are applied in the analysis. By analyzing the results produced by the simulation model for the permanent magnet machine, the guidelines for efficient damper winding parameters for DOL PMSGs are presented. The simulation model is used to simulate grid connections and load transients. The damper winding parameters are calculated by the finite element method (FEM) and determined from experimental measurements. Three-dimensional finite element analysis (3D FEA) is carried out. The results from the simulation model and 3D FEA are compared with practical measurements from two prototype axial flux permanent magnet generators provided with damper windings. The dimensioning of the damper winding parameters is case specific. The damper winding should be dimensioned based on the moment of inertia of the generating set. It is shown that the damper winding has optimal values to reach synchronous operation in the shortest period of time after transient operation. With optimal dimensioning, interferenceon the grid is minimized.
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Biopolttoaineet ovat tärkeä energianlähde suomalaisessa energiantuotannossa. Biopoltto- aineille on kuitenkin ominaista laadun vaihtelevuus. Yksi tärkeimmistä laatutekijöistä on kosteus, joka vaikuttaa myös polttoaineen energiasisältöön. Laatutekijät puolestaan vai- kuttavat polttoainekäsittelyyn, polttoprosessiin ja koko laitoksen hyötysuhteeseen. Tämän työn tarkoituksena oli tutkia voisiko biopolttoaineiden online-laadunmittaus tuoda lisäarvoa energiantuotantolaitokselle. Esimerkkinä käytettiin yhtä online-laadunmittaus- sovellusta, InrayFuel-röntgenmittausjärjestelmää. Sillä voidaan seurata biopolttoaineiden kosteutta ja polttoaineen sisältämiä vierasaineita. Työssä on laadittu kustannusanalyysi, jolla pyritään selvittämään, onko nykyisen kertaluontoisen mittausmenetelmän korvaami- nen jatkuvatoimisella kannattavaa. Esimerkkilaitoksena on Etelä-Savon Energian Pur- sialan voimalaitos, jossa röntgenmittausjärjestelmään on testattu. Saatujen tulosten mukaan investoiminen esimerkkimittausjärjestelmään maksaisi itsensä takaisin alle vuodessa. Kun laitoksella pystytään seuraamaan polttoaineen laatua jatkuva- toimisesti, laadunhallinta paranee ja sitä kautta voidaan saavuttaa kustannussäästöjä. Polt- toaineesta johtuvat häiriötilanteet vähenevät, polttoaine on mahdollista optimoida edulli- semmaksi polton kannalta ja poltto-olosuhteita voidaan säätää paremmin, jolloin päästöt vähenevät ja hyötysuhde kasvaa. Työssä käytetty laskenta analysoi kuitenkin hyvin ylei- sellä tasolla, sillä käytössä ei ollut laitoksen omaa taselaskentajärjestelmää. Laskenta siis sisältää paljon oletuksia. Tämän ja rohkaisevien tulosten vuoksi tutkimusta jatkuvatoimi- sen laadunmittauksen hyödyistä kannattaa tehdä enemmän.
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A method using L-cysteine for the determination of arsenous acid (As(III)), arsenic acid (As(V)), monomethylarsonic acid (MMAA), and dimethylarsinic acid (DMAA) by hydride generation was demonstrated. The instrument used was a d.c. plasma atomic emission spectrometer (OCP-AES). Complete recovery was reported for As(III), As(V), and DMAA while 86% recovery was reported for MMAA. Detection limits were determined, as arsenic for the species listed previously, to be 1.2, 0.8, 1.1, and 1.0 ngemL-l, respectively. Precision values, at 50 ngemL-1 arsenic concentration, were f.80/0, 2.50/0, 2.6% and 2.6% relative standard deviation, respectively. The L-cysteine reagent was compared directly with the conventional hydride generation technique which uses a potassium iodide-hydrochloric acid medium. Recoveries using L-cysteine when compared with the conventional method provided the following results: similar recoveries were obtained for As(III), slightly better recoveries were obtained for As(V) and MMAA, and significantly better recoveries for DMAA. In addition, tall and sharp peak shapes were observed for all four species when using L-cysteine. The arsenic speciation method involved separation by ion exchange .. high perfonnance liquid chromatography (HPLC) with on-line hydride generation using the L.. cysteine reagent and measurement byOCP-AES. Total analysis time per sample was 12 min while the time between the start of subsequent runs was approximately 20 min. A binary . gradient elution program, which incorporated the following two eluents: 0.01 and 0.5 mM tri.. sodium citrate both containing 5% methanol (v/v) and both at a pH of approximately 9, was used during the separation by HPLC. Recoveries of the four species which were measured as peak area, and were normalized against As(III), were 880/0, 290/0, and 40% for DMAA, MMAA and As(V), respectively. Resolution factors between adjacent analyte peaks of As(III) and DMAA was 1.1; DMAA and MMAA was 1.3; and MMAA and As(V) was 8.6. During the arsenic speciation study, signals from the d.c. plasma optical system were measured using a new photon-signal integrating device. The_new photon integrator developed and built in this laboratory was based on a previously published design which was further modified to reflect current available hardware. This photon integrator was interfaced to a personal computer through an AID convertor. The .photon integrator has adjustable threshold settings and an adjustable post-gain device.
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This work consists of a theoretical part and an experimental one. The first part provides a simple treatment of the celebrated von Neumann minimax theorem as formulated by Nikaid6 and Sion. It also discusses its relationships with fundamental theorems of convex analysis. The second part is about externality in sponsored search auctions. It shows that in these auctions, advertisers have externality effects on each other which influence their bidding behavior. It proposes Hal R.Varian model and shows how adding externality to this model will affect its properties. In order to have a better understanding of the interaction among advertisers in on-line auctions, it studies the structure of the Google advertisements networ.k and shows that it is a small-world scale-free network.
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Le réseau Internet s’avère être un outil important pour les juristes. Il rend possible la constitution d’une base de données juridiques, la création de revues de droit, la mise sur pied de forums de discussion sur les questions de droit, la diffusion d’ouvrages, etc. Le réseau Internet facilite les recherches en droit, car grâce aux bases des données, les juristes peuvent facilement accéder notamment aux textes légaux et réglementaires, à la jurisprudence et aux textes de doctrine. Cependant, Internet peut également servir à résoudre les conflits qui surviennent dans les rapports entre les internautes ou entre les internautes et les opérateurs du réseau Internet. La cyberjustice existe déjà, à petite échelle. L’on peut se permettre de mentionner le Centre de médiation et d’arbitrage de l’OMPI, le Virtual Magistrate, l’Online Ombuds Office, le CyberTribunal et le Règlement Uniforme de l’ICANN. S’il faut saluer les efforts qui ont abouti à l’existence de ces instances de cyberjustice, il convient pourtant de reconnaître leurs limites. En effet, ces diverses formes de cyberjustice ont un caractère privé et demeurent incapables d’assurer la répression des infractions. Ensuite, elles ne tiennent pas compte du déséquilibre des rapports entre télétravailleurs et employeurs, puisqu’elles reconnaissent à ces deux groupes des droits équivalents quant au choix de la juridiction et des règles applicables. Enfin, en l’état actuel de la cyberjustice, le sens de la justice est sacrifié à la célérité. Certains droits reconnus aux parties — celui de jouir d’un double degré de juridiction en particulier — sont ignorés. Ces faits montrent bien la nécessité de concevoir des modèles d’institutions plus appropriés en vue de l’instauration d’un certain ordre dans le réseau Internet. C’est dans cette optique que la présente étude offre quelques modèles de juridictions virtuelles, dont une juridiction virtuelle répressive.
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On-line handwriting recognition has been a frontier area of research for the last few decades under the purview of pattern recognition. Word processing turns to be a vexing experience even if it is with the assistance of an alphanumeric keyboard in Indian languages. A natural solution for this problem is offered through online character recognition. There is abundant literature on the handwriting recognition of western, Chinese and Japanese scripts, but there are very few related to the recognition of Indic script such as Malayalam. This paper presents an efficient Online Handwritten character Recognition System for Malayalam Characters (OHR-M) using K-NN algorithm. It would help in recognizing Malayalam text entered using pen-like devices. A novel feature extraction method, a combination of time domain features and dynamic representation of writing direction along with its curvature is used for recognizing Malayalam characters. This writer independent system gives an excellent accuracy of 98.125% with recognition time of 15-30 milliseconds