Synthesis of musical instruments or human voice is a time consuming process which requires theoretical and experimental knowledge about the synthesis engine. Commonly, performers need to deal with synthesizer interfac...
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Synthesis of musical instruments or human voice is a time consuming process which requires theoretical and experimental knowledge about the synthesis engine. Commonly, performers need to deal with synthesizer interfaces and a process of trial and error for creating musical sounds similar to a target sound. This drawback can be overcome by adjusting automatically the synthesizer parameters using optimization algorithms. In this paper a hybrid particle swarm optimization (PSO) algorithm is proposed to solve the frequency modulation (FM) matching synthesis problem. The proposed algorithm takes advantage of a shuffle process for exchanging information between particles and applies the selective passive congregation and the opposition-based learning approaches to preserve swarm diversity. Both approaches for injecting diversity are based on simple operators, preserving the easy implementation philosophy of the particle swarm optimization. The proposed hybrid particle swarm optimization algorithm was validated for a three-nested FM synthesizer, which represents a 6-dimensional multimodal optimization problem with strong epistasis. Simulation results revealed that the proposed algorithm presented promising results in terms of quality of solutions.
Topological insulators is a newly discovered class of materials with the Dirac cone type dispersion at the surface and conventional band in the volume of the material. We present results of the study of the low-freque...
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ISBN:
(纸本)9781457701894
Topological insulators is a newly discovered class of materials with the Dirac cone type dispersion at the surface and conventional band in the volume of the material. We present results of the study of the low-frequency excess noise in thin films made of Bi 2 Se 3 topological insulator material. The films were prepared through mechanically cleavage from the bulk crystal via the “graphene-like” exfoliation procedure. We verified the quality and crystallinity of Bi 2 Se 3 samples with the micro-Raman spectroscopy. Our fabricated devices have linear current voltage characteristics in the low bias region with the current fluctuation noise spectral density SI proportional to 1/f for frequency f less than 10 kHz. The noise spectral density SI showed the square law dependence on the source-drain current and changed from about ~10 -22 to 10 -18 A 2 /Hz as current changes form ~10 -7 to 10 -5 A. Our results can be used for understanding electron transport and trap dynamics, and for reducing low-frequency noise in topological insulator devices.
Sliding mode control (SMC) has been considered as a powerful method for disturbances rejection. On the other hand, we have presented an equivalent-input disturbance (EID) approach to reject disturbances. This paper ta...
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Sliding mode control (SMC) has been considered as a powerful method for disturbances rejection. On the other hand, we have presented an equivalent-input disturbance (EID) approach to reject disturbances. This paper takes a dual-stage feed drive as an example to compare these two methods. The example shows that, while the EID approach obtains almost the same disturbance rejection performance for matched disturbances as that of the SMC does, it can reject unmatched disturbances. This shows the superiority of the EID approach over SMC method.
This work presents a Propositional Dynamic Logic (πDL) in which the programs are described in a language based on the π-Calculus without replication. Our goal is to build a dynamic logic that is suitable for the des...
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Visualization of highway traffic environments in virtual reality plays a key role on fidelity of simulation and validity of driving behaviors in driving simulator studies. This paper describes a procedure to replicate...
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Visualization of highway traffic environments in virtual reality plays a key role on fidelity of simulation and validity of driving behaviors in driving simulator studies. This paper describes a procedure to replicate a signalized intersection with many complex features into a driving simulator's 3-D databases through building a graphical visual database, constructing a road motion database, and creating simulated traffic. The validity of the visualization was assessed via the comparison of the drivers' speeds in the simulator and the speed data at the real intersection. It was found that both speed data follow normal distributions and have equal means for each intersection approach;however, that the speeds measured in the driving simulator have a larger variability than those measured in the field. The users' subjective evaluation results indicated that 92% subjects could recognize the simulated intersection in the driving simulator experiment. Therefore, the strategy of geo-specific environment modeling would be useful for studying driving behaviors in virtual environments.
Business processes modeling projects are increasingly widespread in organizations. Companies have several processes to be identified and modeled. They usually invest much in hiring expert consultants to do such job. H...
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ISBN:
(纸本)9789898425065
Business processes modeling projects are increasingly widespread in organizations. Companies have several processes to be identified and modeled. They usually invest much in hiring expert consultants to do such job. However, they still find no guidelines to help them estimate how much a process modeling project will cost or how long this will take. We propose an approach to estimate the effort required to conduct a BPM project and discuss results obtained from over 50 projects in a large Brazilian company.
Software differs from most manufactured products because it is intangible. This characteristic makes it difficult to detect, control, and understand how it evolves. This paper presents an approach based on software vi...
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Complexity and dynamism of day-to-day activities in organizations are inextricably linked, one impacting the other, increasing the challenges for constant adaptation of the way to organize work to address emerging dem...
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ISBN:
(纸本)9789898425065
Complexity and dynamism of day-to-day activities in organizations are inextricably linked, one impacting the other, increasing the challenges for constant adaptation of the way to organize work to address emerging demands. In this scenario, there are a variety of information, insight and reasoning being processed between people and systems, during process execution. We argue that process variations could be decided in real time, using context information collected. This paper presents a proposal for a business process line cycle, with a set of activities encapsulated in the form of components as central artefact. We explain how composition and adaptation of work may occur in real time and discuss a scenario for this proposal.
The idea of a Kripke semantics endowed with possibility/plausibility information is not new; in fact there are different approaches for that; see: [6], [13], [16], [19]. This paper follows the approach found in [6], b...
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The idea of a Kripke semantics endowed with possibility/plausibility information is not new; in fact there are different approaches for that; see: [6], [13], [16], [19]. This paper follows the approach found in [6], but whereas [6] provides a fixed interpretation for connectives into [0,1] here we provide a characterization of a fuzzy semantics for connectives in such a way that the resulting fuzzy frames: K, T and D, are described precisely by the set of statements which also describes, respectively, the usual modal systems K, T and D.
作者：
Magdaleno, Andréa MagalhãesCOPPE/PESC
System Engineering and Computer Science Program UFRJ Rio de Janeiro Brazil NP2Tec
Research and Practice Group in Information Technology UNIRIO Rio de Janeiro Brazil
A major activity performed by the manager before starting a software project is tailoring its development process. Such activity requires information about the context under which the project will be executed, includi...
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