Improved control strategy of DFIG-based wind turbines using direct torque and direct power control techniques

This paper presents different control strategies for a variable-speed wind energy conversion system (WECS), based on a doubly fed induction generator. Direct Torque Control (DTC) with Space-Vector Modulation is used on the rotor side converter. This control method is known to reduce the fluctuations of the torque and flux at low speeds in contrast to the classical DTC, where the frequency of switching is uncontrollable. The reference for torque is obtained from the maximum power point tracking technique of the wind turbine. For the grid-side converter, a fuzzy direct power control is proposed for the control of the instantaneous active and reactive power. Simulation results of the WECS are presented to compare the performance of the proposed and classical control approaches.Peer reviewedFinal Accepted Versio

Appointments, pay and performance in UK boardrooms by gender

This article uses UK data to examine issues regarding the scarcity of women in boardroom positions. The article examines appointments, pay and any associated productivity effects deriving from increased diversity. Evidence of gender-bias in the appointment of women as non-executive directors is found together with mixed evidence of discrimination in wages or fees paid. However, the article finds no support for the argument that gender diverse boards enhance corporate performance. Proposals in favour of greater board diversity may be best structured around the moral value of diversity, rather than with reference to an expectation of improved company performance

Contemporary trends in development of active substances possessing the pesticidal properties: spinosyn insecticides

A new group of insecticides belonging to the category of bio-pesticides, namely – spinosyns, is discussed. The spinosyns are the products of bacterial fermentation by microorganisms Saccharopolyspora spinosa (Actinomycetes group) in a nutrient media. The chemical structures of spinosyns, also those developed by the semi-synthetic and biochemical modifications, as well as their insecticidal properties and mechanism of biological activity, the range of their application in crop protection and the commercially available products based on them, are reviewed

Contemporary trends in development of active substances possessing the pesticidal properties: ryanodine-receptor targeting insecticides

The latest developed classes of synthetic insecticides – phthalic acid diamides and antranilic diamides, acting as ryanodine receptor modulators, are discussed. The mode of their activity, the insecticidal properties and characteristics of their representatives is reviewed

Board gender diversity and corporate environmental performance: the moderating role of family and dual class majority ownership structures

While prior work has investigated the impact of (a) ownership structure and (b) board gender diversity separately on corporate environmental performance, researchers have not studied the potentially important relationship between ownership control and female board diversity in influencing corporate environmental performance jointly. We do so in the context of majority ownership in family controlled and dual class firms whose motives and influence are theoretically different from that of the firm’s minority shareholders. Drawing on resource dependency, socio-emotional wealth theory, and secondary agency theory, we hypothesize that majority family owners and dual class owners likely choose women directors to help advance their personal preferences for environmental CSR. Our empirical tests utilizing 2755 US firmyears over the 2010-2015 show that, as hypothesized, these two majority ownership types interact with board gender diversity to positively influence corporate environmental performance

Recommendation on Measures to Safeguard Freedom of Expression and Undistorted Competition in EU Trade Mark Law

Whatever the protection afforded to trade marks, it must always be balanced against general interests, in particular the fundamental freedom of expression and the guarantee of undistorted competition, as reflected in the Lisbon Treaty, the Charter of Fundamental Rights and the European Convention on Human Rights. The need for an appropriate balance is inherent in trade mark law. It is an issue of particular importance in the light of ongoing technological, economic and social developments, and of considerable complexity because of the diversity of legitimate interests of trade mark proprietors, consumers, competitors and the public at large. Against this background, the Recommendation provides guidance on how to offer sufficient room for freedom of expression and freedom of competition in the envisaged new EU trade mark legislation. It addresses measures to be taken by legislators, trade mark registration offices and the courts at various stages: from the grant of trade mark rights and the analysis of trade mark infringement to limitations of trade mark protection and the appropriate distribution of the burden of proof