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Learning Profile Identification Based on the Analysis of the User Context of Interaction

Zaina, Luciana Aparecida Martinez; Bressan, Graca; Junior, José Fernando Rodrigues; Cardieri, M. A. C. A.
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Artigo de Revista Científica
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One of the e-learning environment goal is to attend the individual needs of students during the learning process. The adaptation of contents, activities and tools into different visualization or in a variety of content types is an important feature of this environment, bringing to the user the sensation that there are suitable workplaces to his profile in the same system. Nevertheless, it is important the investigation of student behaviour aspects, considering the context where the interaction happens, to achieve an efficient personalization process. The paper goal is to present an approach to identify the student learning profile analyzing the context of interaction. Besides this, the learning profile could be analyzed in different dimensions allows the system to deal with the different focus of the learning.

Adaptive Approach for a Maximum Entropy Algorithm in Ecological Niche Modeling

RODRIGUES, E. S. C.; RODRIGUES, F. A.; ROCHA, R. L. A.; CORREA, P. L. P.
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Artigo de Revista Científica
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This paper presents an Adaptive Maximum Entropy (AME) approach for modeling biological species. The Maximum Entropy algorithm (MaxEnt) is one of the most used methods in modeling biological species geographical distribution. The approach presented here is an alternative to the classical algorithm. Instead of using the same set features in the training, the AME approach tries to insert or to remove a single feature at each iteration. The aim is to reach the convergence faster without affect the performance of the generated models. The preliminary experiments were well performed. They showed an increasing on performance both in accuracy and in execution time. Comparisons with other algorithms are beyond the scope of this paper. Some important researches are proposed as future works.

A Procedure for Semantic Querying in the Adaptive Formalism

CHAER, I.; ROCHA, R. L. A.
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Artigo de Revista Científica
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This paper contains a new proposal for the definition of the fundamental operation of query under the Adaptive Formalism, one capable of locating functional nuclei from descriptions of their semantics. To demonstrate the method`s applicability, an implementation of the query procedure constrained to a specific class of devices is shown, and its asymptotic computational complexity is discussed.

Optimization of the Topology of Electric Energy Distribution Networks by Using Algorithm Inspired on Ant Behaviors

ZAMBONI, L.; MONTEIRO, L. H. A.
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Artigo de Revista Científica
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An algorithm inspired on ant behavior is developed in order to find out the topology of an electric energy distribution network with minimum power loss. The algorithm performance is investigated in hypothetical and actual circuits. When applied in an actual distribution system of a region of the State of Sao Paulo (Brazil), the solution found by the algorithm presents loss lower than the topology built by the concessionary company.

Equivalent Circuits and Nanoplasmonics

NUNES, Frederico D.; WEINER, John
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Artigo de Revista Científica
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We show how a circuit analysis, used widely in electrical engineering, finds application to problems of light wave injection and transport in subwavelength structures in the optical frequency range. Lumped circuit and transmission-line analysis may prove helpful in the design of plasmonic devices with standard, functional properties.; Fundacao de Amparo A Pesquisa do Estado de Sao Paulo (FAPESP); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Centro de Pesquisa em Optica e Fotonica (CePOF) at the Universidade de Sao Paulo (USP), Sao Carlos, SP, Brazil, in 2007; Centro de Pesquisa em Optica e Fotonica (CePOF) at the Universidade de Sao Paulo (USP), Sao Carlos, SP, Brazil, in 2007

Improving the Robustness of Distributed Failure Detectors in Adverse Conditions

Lemos, Fernando Tarla Cardoso; Sato, Liria Matsumoto
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC; PISCATAWAY Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC; PISCATAWAY
Tipo: Artigo de Revista Científica
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Failure detection is at the core of most fault tolerance strategies, but it often depends on reliable communication. We present new algorithms for failure detectors which are appropriate as components of a fault tolerance system that can be deployed in situations of adverse network conditions (such as loosely connected and administered computing grids). It packs redundancy into heartbeat messages, thereby improving on the robustness of the traditional protocols. Results from experimental tests conducted in a simulated environment with adverse network conditions show significant improvement over existing solutions.

Perceptual Annotation: Measuring Human Vision to Improve Computer Vision

Scheirer, Walter Jerome; Anthony, Samuel English; Nakayama, Ken; Cox, David Daniel
Fonte: Institute of Electrical & Electronics Engineers (IEEE) Publicador: Institute of Electrical & Electronics Engineers (IEEE)
Tipo: Artigo de Revista Científica
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For many problems in computer vision, human learners are considerably better than machines. Humans possess highly accurate internal recognition and learning mechanisms that are not yet understood, and they frequently have access to more extensive training data through a lifetime of unbiased experience with the visual world. We propose to use visual psychophysics to directly leverage the abilities of human subjects to build better machine learning systems. First, we use an advanced online psychometric testing platform to make new kinds of annotation data available for learning. Second, we develop a technique for harnessing these new kinds of information – “perceptual annotations” – for support vector machines. A key intuition for this approach is that while it may remain infeasible to dramatically increase the amount of data and high-quality labels available for the training of a given system, measuring the exemplar-by-exemplar difficulty and pattern of errors of human annotators can provide important information for regularizing the solution of the system at hand. A case study for the problem face detection demonstrates that this approach yields state-ofthe- art results on the challenging FDDB data set.; Engineering and Applied Sciences; Molecular and Cellular Biology

Synthesis, analysis, and processing of fractal signals Gregory W. Wornell.

Fonte: Research Laboratory of Electronics, Massachusetts Institute of Technology Publicador: Research Laboratory of Electronics, Massachusetts Institute of Technology
Formato: 239 p.; 12111490 bytes; application/pdf
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Also issued as Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1991.; Includes bibliographical references (p. 234-239).; Supported by the Defense Advanced Research Projects Agency. N00014-89-J-1489 Supported by the Air Force Office of Scientific Research. AFOSR 91-0034 Supported by the National Science Foundation. MIP 87-14969 Supported by Lockheed Sanders, Inc.

Representation of consonants in the peripheral auditory system : a modeling study of the correspondence between response properties and phonetic features

Fonte: Massachusetts Institute of Technology, Research Laboratory of Electronics Publicador: Massachusetts Institute of Technology, Research Laboratory of Electronics
Formato: 276 p.; 14981674 bytes; application/pdf
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Richard Scott Goldhor.; Also issued as Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1985.; Includes bibliographical references (p. 267-276).; Supported in part by the National Science Fopundation. MCS 81-128899

The numerical synthesis and inversion of acoustic fields using the Hankel transform with application to the estimation of the plane wave reflection coefficient of the ocean bottom

Fonte: Massachusetts Institute of Technology, Research Laboratory of Electronics Publicador: Massachusetts Institute of Technology, Research Laboratory of Electronics
Formato: 226 p.; 8241090 bytes; application/pdf
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Douglas R. Mook.; Originally published as thesis (Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, M.S., 1984).; Includes bibliographical references.; Advanced Research Projects Agency Contract no. N00014-81-K-0742 NR-049-506 National Science Foundation Grant ECS80-07102

Iterative algorithms for optimal signal reconstruction and parameter identification given noisy and incomplete data

Fonte: Massachusetts Institute of Technology, Research Laboratory of Electronics Publicador: Massachusetts Institute of Technology, Research Laboratory of Electronics
Formato: 466 p.; 23092038 bytes; application/pdf
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Bruce Ronald Musicus.; Originally published as thesis (Dept. of Electrical Engineering and Computer Science, Ph.D., 1982).; Includes bibliographies.; Supported in part by the Advanced Research Projects Agency monitored by ONR under Contract N00014-81-K-0742 NR-049-506 Supported in part by the National Science Foundation under Grant ECS80-07102

6.071 Introduction to Electronics, Fall 2002; Introduction to Electronics

Cory, David G.; Freidberg, Jeffrey P.; Parmelee, Elizabeth W.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 17565 bytes; 15135 bytes; 17436 bytes; 17156 bytes; 14248 bytes; 14506 bytes; 12917 bytes; 16936 bytes; 11 bytes; 4586 bytes; 21366 bytes; 11602 bytes; 38351 bytes; 4755 bytes; 27322 bytes; 25313 bytes; 4039 bytes; 301 bytes; 354 bytes; 339 bytes; 180 byt
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Introductory subject suitable for students with little or no previous background in electronics. Elementary network theory with op-amps, transients, second order linear systems and active filters, AM and FM modulation, diode and transistor circuits, design of digital circuits. Examples emphasize practical uses of electronics in experimental science. Alternate week laboratory.

Migration from electronics to photonics in multicore processor

Xu, Zhoujia
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 54 leaves
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Twenty - first opportunities for Gigascale Integration will be governed in part by a hierarchy of physical limits on interconnect. Microprocessor performance is now limited by the poor delay and bandwidth performance of the on - chip global wiring layer. This thesis is envisioned as a critical showstopper of electronic industry in the near future. The physical reason behind the interconnect bottleneck is the resistive nature of metals. The introduction of copper in place of aluminum has temporarily improved the interconnect performance, but a more disruptive solution will be required in order to keep the current pace of progress, optical interconnect is an intriguing alternative to metallic wires. Many - core microprocessors will push performance per chip from the 10 gigaflop to the 10 teraflop range in the coming decade. Pin limitations, the energy cost of electrical signaling, and the non - scalability of chip - length global wires are significant bandwidth impediments. Silicon nanophotonic based many core architecture are introduced in order to meet the bandwidth requirements at acceptable power levels.; by Zhoujia Xu.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008.; Includes bibliographical references (leaf 54).

The Global Opportunity in IT-Based Services : Assessing and Enhancing Country Competitiveness

Sudan, Randeep; Ayers, Seth; Dongier, Philippe; Muente-Kunigami, Arturo; Qiang, Christine Zhen-Wei
Fonte: World Bank Publicador: World Bank
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This book aims to help policy makers take advantage of the opportunities presented by increased cross-border trade in information technology (IT) services and IT-enabled services (ITES). It begins by defining the two industries and estimating the potential global market opportunities for trade in each. Then it discusses economic and other benefits for countries that succeed in these areas, along with factors crucial to the competitiveness of a country or location, including skills, cost advantages, infrastructure, and a hospitable business environment, and examines the potential competitiveness of small countries and of least developed countries specifically. The volume also discusses policy options for enabling growth in the IT services and ITES industries. Appendix A introduces the Location Readiness Index (LRI), a modeling tool to help countries assess their IT and ITES industries. Finally, appendix B presents an analysis of the IT and ITES industries in Indonesia and Kenya as an illustrative application of the LRI.

A survey on the contributions of power electronics to smart grid systems

COLAK ILHAMI; KABALCI Ersan; FULLI Gianluca; LAZAROU STAVROS
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Articles in periodicals and books Formato: Online
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The smart grid (SG) as a research area is advancing dealing with a wider range of topics such as power systems, energy generation and telecommunication. The conventional utility grid used to operate in a passive mode absorbing energy from the substations and delivering it to the customers. This approach is well developed but the needs of the state-of-the-art technology require a bidirectional flow of power and data. Nevertheless, smart grid systems provide more flexible, reliable, sustainable, secure and two-way communication service. Especially, integration of renewable energy sources, electrical vehicles and distributed generations (DG) in to network can be achieved in an efficient way in smart grid system. Moreover, control and monitoring capabilities, automatic configuration of the grid, actively involving of consumers in energy production extend the importance of smart grids. All these positive aspects of smart grids have been attained by integration of power electronics and telecommunication technologies with the grid. This study deals with contributions of power electronics to SG in the context of generation, conversion, distribution, and control of power. The recent power electronic devices and systems adapted to SG are also introduced in detail with several power control methods. Moreover...

Performance virtualization and QoS in shared storage systems

Gulati, Ajay
Fonte: Universidade Rice Publicador: Universidade Rice
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To handle the growing demands of data intensive applications, storage consolidation is becoming an attractive organizational paradigm. The benefits of consolidation include universal data access, sharing among users, flexibility in allocation and provisioning, and economies of centralized infrastructure management. While high-end storage arrays deliver high performance and reliability, they generally lack support for providing quality of service (QoS) guarantees. Providing best effort service alone may no longer be sufficient in future shared storage systems serving diverse client workloads. Consequently, there is a growing need for storage systems to provide mechanisms for isolating applications from each other and providing differentiated QoS to them based on their needs. Existing approaches for QoS provisioning in storage servers fall into three different categories: (1) Bandwidth allocation mechanisms, (2) Time slicing at the devices, and (3) Control theoretic approaches. However all of these approaches have shortcomings that discourage their practical use. The challenges include dealing with bursty workloads, access locality, variable workload-dependent server capacity, and the impact of fairness mechanisms on overall throughput. This dissertation makes two major contributions towards making QoS in storage systems a reality and bridging the gap between theory and practice. First...

Phase transitions and diffusion of colloid-polymer systems and thin ferroelectric films for device applications

Lee, Jiun-Ting
Fonte: Universidade Rice Publicador: Universidade Rice
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This thesis is divided into two independent parts: the first part deals with the phase transitions and diffusion of colloid-polymer systems, while the second part concerns the growth of thin ferroelectric films, their physical and chemical characterizations, and theoretical predictions for surface-acoustic-wave (SAW) propagation. In the first part, the phase transitions of colloid-polymer systems are studied by experiment and theory in both two and three dimensions. For a colloid-polymer system consisting of polystyrene spheres in aqueous solutions of hydroxyethylcellulose, the transitions are examined experimentally using enhanced videomicroscopy with particle resolution, and the results are compared with statistical mechanical predictions based on the Percus-Yevick and mean-field approximations. The Brownian motion of colloidal particles in polymer solutions is also investigated for the system of colloid (polystyrene)-polymer (polyethyleneoxide), and the diffusivity is determined as a function of polymer concentration. In the second part, thin films of the ferroelectric lithium niobate are deposited by radio-frequency magnetron sputtering on diamond-coated silicon substrates for high-frequency SAW-device applications. The SAW velocity and electromechanical coupling coefficient are predicted theoretically for various film orientations and thicknesses. Moreover...

The case for vehicular visible light communication (V2LC): Architecture, services and experiments

Liu, Cen Bi
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: application/pdf
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Visible Light Communications (VLC) is a fast-growing technology to provide data communication using low-cost and omni-present LEDs and photodiodes. In this thesis, we make the case for the use of vehicular VLC (V2LC) as follows. We describe an architecture for V2LC networks and introduce five network services that V2LC needs to provide for vehicular applications. We use a custom VLC prototype developed at Intel on which we investigate the unique networking properties of V2LC. Specifically, our experiments show that a V2LC receiver's narrow filed-of-view angle makes V2LC resilient to visible light noise from sunlight and legacy LED sources and interference from active VLC transmitters; further, V2LC can operate in full-duplex mode with the exception of being subject to multipath effects at very short distances, e.g., 1.5 m in our experiment. By performing a large scale simulation study and leveraging our experimental data, we evaluate V2LC's ability to provide network services for vehicular applications. Our results reveal two key findings: (i) in dense vehicle traffic conditions (e.g., urban highway during peak hours), V2LC takes advantage of multiple available paths to reach vehicles and overcomes the effects of packet collisions; (ii) in the presence of a visible light blockage in traffic...

Algorithm for Missing Values Imputation in Categorical Data with Use of Association Rules

Kaiser, Jiří
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/11/2012 Português
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This paper presents algorithm for missing values imputation in categorical data. The algorithm is based on using association rules and is presented in three variants. Experimental shows better accuracy of missing values imputation using the algorithm then using most common attribute value.; Comment: 4 pages, 3 tables, 2011 Third International Joint Journal Conference in Computer, Electronics and Electrical, ACEEE International Journal on Recent Trends in Engineering & Technology, Vol. 06, Is. 01, Nov 2011

Design, optimization, analysis and control topics in nanotechnology ad MEMS courses

Lyshevski, Sergey; Fuller, Lynn
Fonte: IEEE Publicador: IEEE
Tipo: Proceedings
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This paper discusses the use of a systems theory, design coverage and control topics in nanotechnology and microelectromechanical systems (MEMS) courses developed and offered in the College of Engineering in RIT. The multidisciplinary nano and microengineering have accomplished a phenomenal growth over the last twenty years due to the rapid advances in microelectronics, molecular technologies, bulk and surface micromachining, computer-aided-design (CAD), etc. Recent fundamental and applied research and developments in molecular electronics and informatics have been notably contributed to the current progress. Enabling nano/micro engineering utilizes and depends on the fundamentals, software and hardware. These prominent developments largely depend on modern engineering and science providing the end-users with the needed technologies and design concurrency. With the increasing demands in high-performance envisioned nanosystems and emerged microsystems, designers apply new concepts. The role of nanotechnology and MEMS courses in the engineering curriculum is examined. We discuss the integration of design, optimization, control and analysis topics in Nano Science, Engineering and Technology (NanoSET) and MEMS courses. The MEMS curriculum consists of three courses...