Abstract
The most relevant aspects related to the phase mask dithering/moving method for the fabrication of complex Bragg grating designs are reviewed. Details for experimental implementation of this technique is presented, including theoretical analysis of the calibration functions for the correct dither/displacement. Results from tailored Bragg grating structures fabricated by this method are shown. Apodized Bragg gratings with modeled spatial profiles were implemented, resulting in side mode suppression levels of more than 20 dB in gratings showing transmission filtering level higher than 30 dB. Chirped gratings with the spectral bandwidth up to 4 nm, p-shift and sampled Bragg gratings with equalized peaks equally spaced by 0.8 nm (100 GHz) were also fabricated. © 2012 The Author(s).

Abstract
This paper presents a tool, named QUERYSHEET, to query spreadsheets. We defined a language to write the queries, which resembles SQL, the language to query databases. This allows to write queries which are more related to the spreadsheet content than with current approaches.

Abstract
Searching for resources over unstructured networks is usually supported by broadcast communication primitives. Ideally, the broadcast process should be cancelled as soon as possible after a successful discovery, to avoid flooding the entire network. However, cancelling an ongoing broadcast is challenging and may increase the number of exchanged messages. In this paper, we compare the cancellation mechanisms used by BERS and BERS^* with new proposed cancellation approaches BCIR and BCIR^*. The formulation of a simplified analytical model and the simulation results show that: i) it is possible to reduce the number of retransmitted messages, without increasing the latency observed in BERS^*; and ii) BCIR is more energy efficient, which can contribute to extend the availability of mobile battery powered devices. Copyright 2013 ACM.

Abstract
In the classical model of the photovoltaic (PV) cell/module, based on the single-exponential or double-exponential representation of PV cell/module behavior, parasitic parameters are ignored. Their presence, however, has multiple effects, such as the maximum power point tracking on the current-voltage curve, the switching ON/OFF of the inverters for grid connection, and the electrical safety of persons against indirect contact due to ground leakage currents and lightning phenomena. The effects of parasitic parameters can be visualized in the experimental results gathered through the transient charge of an external capacitor connected to the PV generator terminals. The impact of the parasitic components is different when considering a single PV module or a PV array composed of several PV modules. At the module scale, an oscillation occurs in the initial part of the current waveform, which indicates the presence of some inductive components. At the array scale, the inductive phenomena are overdamped, and parasitic capacitive effects become predominant. This paper shows how to determine the parameters of an extended model of PV modules embedding the parasitic parameter effects. It starts from the experimental results obtained from the fast-sampled voltage and current waveforms during the transient charge of an external capacitor. Numerical examples taken from real cases with different PV technologies are provided.

Abstract
In this article, an algorithm to identify LPV State Space models is proposed. The LPV State Space system is in the companion reachable canonical form. Both the state matrix and the output vector coefficients are linear combinations of a set of nonlinear basis functions dependent on the scheduling signal. This model structure, although simple, can describe accurately the behaviour of many nonlinear systems by an adequate choice of the scheduling signal. The identification algorithm minimises a quadratic criterion of the output error. Since this error is a linear function of the output vector parameters, a separable nonlinear least squares approach is used to minimise the criterion function by a gradient method. The derivatives required by the algorithm are the states of LPV systems that need to be simulated at every iteration. The effectiveness of the algorithm is assessed by two simulated examples.

Abstract
Context: Keyword research is a widely used resource for retrieving information through search engines available on the Internet. However, most of the information available in the world fails to be obtained by conventional search processes due to its storage in databases, most of them relational. Studies that offer effective solutions when these data sources include relational databases have not been found in the literature. Objective: To present a solution for retrieving information stored in heterogeneous data sources using the OAI-PMH protocol as a mechanism that promotes interoperability. Method: Implementing a system that runs keyword queries in heterogeneous data sources through the collection of metadata exposed to OAI-PMH in data providers. Also, this study proposes a web service that uses public methods to allow relational database information to be returned without the need for additional efforts. Results: The simulations produced a return of information from metadata of digital objects and relational databases, obtained by data providers. Running query examples was successful in retrieving information in all data sources surveyed. Conclusion: This study proposes a solution for retrieving information stored in heterogeneous data sources. The proposed solution proved feasible by allowing keyword research in digital libraries and relational databases using OAI-PMH.