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Acknowledgements: This report was made possible with the support of Bayer Healthcare. To guarantee the independence of the report and the working group's conclusions, the content of this report was developed exclusively by the authors, without any influence from Bayer HealthCare, The herein opinions do not reflect Bayer HealthCare's position or opinion. The working group did not receive any honoraria to participate in the development of this report. [ABSTRACT FROM AUTHOR]

In this work, we propose a novel constructive method to deal with the unweighted minimum string cover problem. Given a set of strings S , this defiant optimization problem aims to find a minimum set of substrings M from S such that every string in S can be written as a concatenation of the strings in M . This problem has challenging real-world applications, especially in the field of computational biology. The proposed constructive algorithm is composed of two stages that are executed iteratively. The objective of the first stage is to find frequent substrings in S to be included in M . The aim of the second stage is to simplify the set M to try to get a minimal set. Extensive computational experiments reveal that the proposed algorithm is highly effective for solving complex instances involving up to 100 000 strings in S as compared to the current state-of-the-art method. [ABSTRACT FROM AUTHOR]

Abstract—This article shows a method to optimize the reliability of an electric power system by the introduction of distributed generation. The reliability index of the system is determined as the failure probability of the system. A hybrid method that uses a binary shuffled frog-leaping algorithm and probabilistic load flow is proposed to search a large number of combinations for location and size of biomass power plants and photovoltaic units. The combination with the best performance minimizes the reliability index (probability of failure) of the system. [ABSTRACT FROM PUBLISHER]

The isothermal crystallization of poly(ethylene terephthalate) (PET) homopolymers with different molecular weight was studied in a wide temperature range (140-230 °C) using different experimental techniques. Three different morphological regions, labeled r1, r2 and r3, were distinguished as a function of crystallization temperature (Tc). In r1 (low Tc) crystallized samples were characterized by a low crystalline degree with a small spherulite texture containing thin crystals. In r2 (intermediate Tc) samples showed medium size spherulites composed of two distinct crystalline families (thin and thick crystals). In this temperature range, the crystallization exhibited a maximum value and it was associated with a high content of secondary crystals. In r3 (high Tc), samples presented considerable amorphous zones and regions consisting of oversized spherulites containing only thick crystals. Time-resolved wide-angle X-ray diffraction measurements, using synchrotron radiation, indicated a rapid evolution of the crystalline degree within the second region, incontrast with the quite slow evolution observed in the third region. On the other hand, by small-angle X-ray scattering (SAXS) and time-resolved SAXS experiment, it was found that the long period (L) as well as the lamellar thickness (lc) increase as a function of Tc, corroborating the formation of the thickest crystals in the third region. From all these observations, a morphological model was proposed for each region. [ABSTRACT FROM AUTHOR]

Predictive control is generating considerable interest when it comes to implementing current control strategies in power converters. Remarkable accuracy and fast dynamic response are its main characteristics. However, this technique is computationally demanding compared to classic control schemes. This is particularly true in multilevel converters, where several variables of the system such as currents, switching frequency and neutral-point voltage balancing, to name a few, are controlled simultaneously. An important issue is to reduce the delay between the variable sampling and the instant at which the switching state is applied to the converter. Although DSP-based implementations have been proven to be an effective solution, the parallel nature of predictive controllers better fits with the architecture of field-programmable gate array (FPGA) devices. This paper presents a new approach to the FPGA-based implementation of a predictive current controller for a multilevel converter. This approach also aims to reduce the average switching frequency and obtain neutral-point voltage balancing. The switching state is applied in the same sampling period in which the controlled variables are measured thereby enhancing the dynamic response of the system. [ABSTRACT FROM PUBLISHER]

This paper presents a current control scheme for a voltage-source converter connected to the grid through an LCL filter. The proposed current control is based on the linear quadratic (LQ) Gaussian (LQG) servo controller technique, which combines the LQ regulator and the Kalman filter (KF). The use of the KF instead of a Luenberger estimator improves the quality of the estimation of state variables in noisy environments, increasing the noise immunity of the control loop. This paper focuses on giving some criteria and practical hints to choose both the KF and LQ design parameters to achieve null steady-state tracking error, channel decoupling, and noise immunity. Furthermore, this paper analyzes the steady-state KF approximation that allows a significant decrement in the computational complexity of the algorithm at nearly no cost in accuracy. Simulation and experimental results prove the correct operation of the proposed LQG current control and the possible advantages of using KF to estimate the state vector. [ABSTRACT FROM PUBLISHER]

We review the state-of-the art regarding the second-order nonlinear optical response of metal nanostructures and metamaterials. The present nanofabrication of metal nanostructures gives rise to defects and other deviations from the ideal structure. Such factors may break the intended symmetry of the structure and give rise to nonlinear signals, which are ideally forbidden. Although second-order effects are electric-dipole forbidden in the bulk of centrosymmetric materials, they become allowed through magnetic-dipole and electric-quadrupole effects. Improved understanding of the role of the surface and bulk effects in the second-order response of metals is needed in order to develop proper theoretical models for nonlinear metal nanostructures. [ABSTRACT FROM AUTHOR]

The objective of this study was to test whether the Blatant and Subtle Prejudice Scales of Meertens and Pettigrew (1992) are valid for the evaluation of prejudicial attitudes in Spanish school-based adolescents. To do so gypsies and immigrants were chosen as two exogroups that might be the object of prejudice among the Spanish population. Participants were 1,378 Spanish school-based adolescents in the Autonomous Community of the Principality of Asturias, Spain. The results indicate that the scales present a factor structure different from that of the original study. Also, covariates of both blatant and subtle prejudice scales scores were explored. A different pattern of relationships between covariates and scores on blatant and subtle prejudice were found. [ABSTRACT FROM AUTHOR]

This letter proposes a new control scheme for the neutral-point (NP) balance in single-phase three-level NP-clamped converters. The control is addressed considering the plant under study, a nonlinear time-variant system. A quasi-exact linearization is applied allowing the application of classic control techniques. The described method is simple, general, and suitable for buck and boost topologies, as well as for inverter or rectifier operating modes under either linear or nonlinear loading. Correct operation is verified under simulated and experimental operation. [ABSTRACT FROM AUTHOR]

This paper proposes a grid impedance monitoring system for distributed power generation electronic interfaces. The system estimates the grid equivalent impedance and voltage source from the voltage measurements performed at the point of common coupling. The estimation algorithm is based on a recursive least-squares algorithm implemented in the complex field. Simultaneously, the system evaluates the quality of the estimation, minimizing its influence on the grid and detecting islanding situations. The proposed system performance has been evaluated under experimental testing. [ABSTRACT FROM AUTHOR]

As the number of wind power applications with power electronic interfaces in the grid increases, it is becoming unacceptable to disconnect the generating units every time disturbances occur, especially under voltage dips, as was a common practice in the past. Keeping the converter online during unbalanced voltage, and guaranteeing the actual standards of the converter connected to the grid, is becoming a very critical issue. From these goals, the design of a robust back-to-back neutral point clamped (three levels) voltage source converter of 150 kVA is developed in this paper. The converter is divided into two main parts: the power electronic system and the control electronic system. Concerning the first part, on the one hand, the paper presents the designs of active and passive components as insulated gate bipolar transistor, free-wheeling diodes, clamping diodes, grid filter, dc-bus capacitors, etc.; and on the other hand, the converter requirements are analyzed to ride through real grid conditions, i.e., unbalanced voltage dips. Concerning the control electronic system, the chosen electronic structure and the task distribution between the two processors used are shown. [ABSTRACT FROM AUTHOR]

Evaluates the role of glial cell-line derived neurotrophic factor and neurotrophins in the development of locus coeruleus (LC) noradrenergic (NA) neurons. Generation of double null mutant mice; Loss of NA LC neurons in the TrkB null mutant mice; Proliferation of cells in the LC.