1,002 research outputs found
Selective virtual capacitive impedance loop for harmonic voltage compensation in islanded microgrids
Parallel inverters having LCL output filters cause
voltage distortions at the point of common coupling (PCC)
in islanded microgrids when non-linear loads are present. A
capacitive virtual impedance loop could be used to provide
selective harmonic compensation in islanded microgrids, instead
of introducing additional active or passive filters into the system
that could compromise the stability of the microgrid. However,
the performance of these compensation loops becomes degraded
when a virtual resistance is introduced with the aim to improve
the overall stability of the parallel inverters. With the capacitive
virtual impedance, there is effectively a compromise between
the additional stability provided by the virtual resistance and
the harmonic compensation due to the virtual capacitance. This
paper focuses on overcoming this limitation of the capacitive
virtual impedance with additional virtual resistance for selective
harmonic compensation in islanded microgrids. Simulation results
were given to show the suitability of the proposed algorithms
in reducing the voltage harmonics at the PCC.peer-reviewe
A generation apart? Youth and political participation in Britain
Conventional wisdom holds that young people in Britain are alienated from politics, with some claiming that this reflects a wider crisis of legitimacy that should be met by initiatives to increase citizenship. This article addresses these areas, presenting both panel survey and focus group data from first-time voters. It concludes that, contrary to the findings from many predominantly quantitative studies of political participation, young people are interested in political matters, and do support the democratic process. However they feel a sense of anti-climax having voted for the first time, and are critical of those who have been elected to positions of political power. If they are a generation apart, this is less to do with apathy, and more to do with their engaged scepticism about âformalâ politics in Britain
Low pay and the living wage
Editorial Introducing Special Issue of Employee Relation
Using Cognitive Interviewing for the Semantic Enhancement of Multi-Lingual Versions of Personality Questionnaires
We discuss the use of cognitive interviewing with bilinguals as an integral part of cross-cultural adaptation of personality questionnaires. The aim is to maximize semantic equivalence to increase the likelihood of items maintaining the intended structure and meaning in the target language. We refer to this part of adaptation as semantic enhancement, and integrate cognitive interviewing within it as a tool for scrutinizing translations, the connotative meaning, and the psychological impact of items across languages. During the adaptation of a work-based personality questionnaire from English to Arabic, Chinese (Mandarin), and Spanish, we cognitively interviewed 12 bilingual participants about 136 items in different languages (17% of all items), of which 67 were changed. A content analysis categorizing the reasons for amending items elicited eleven errors that affect two identified forms of semantic equivalence. We provide the resultant coding scheme as a framework for designing cognitive interviewing protocols and propose a procedure for implementing them. We discuss implications for theory and practic
Women in management- onwards and upwards A survey outlining the position of women in management today: special report
3.00SIGLELD:81/18761(Women). / BLDSC - British Library Document Supply CentreGBUnited Kingdo
- âŠ