Intercircuit faults and distance relaying of dual-circuit lines

The main sources of error and other difficulties associated with the distance protection of dual-circuit transmission lines are well known. However, the design or selection of protection schemes usually fails to consider some of the more extraordinary faults that do occur. This pape r considers the observed impedances that result from intercircuit faults on a simulated dual-circuit transmission line, where variations in the phasing as well as the impedance ratios have been considered. The simulations performed with the Alternative Transients Program show that intercircuit faults may be undetectable in the instantaneous protection zone depending on the scheme adopted and the impedances of the surrounding network. The observed under-reaching has the potential to lead to a loss of major loads, maloperation of single-pole tripping schemes and even system instabilities based on the critical clearance requirements. © 2005 IEEE

Disaster warning system: Satellite feasibility and comparison with terrestrial systems. Volume 1: Executive summary

The Disaster Warning System (DWS) is a conceptual system which will provide the National Weather Service (NWS) with communication services in the 1980s to help minimize losses caused by natural disasters. The object of this study is a comparative analysis between a terrestrial DWS and a satellite DWS. Baseline systems satisfying the NOAA requirements were synthesized in sufficient detail so that a comparison could be made in terms of performance and cost. The cost of both baseline systems is dominated by the disaster warning and spotter reporting functions. An effort was undertaken to reduce system cost through lower-capacity alternative systems generated by modifying the baseline systems. By reducing the number of required channels and modifying the spotter reporting techniques, alternative satellite systems were synthesized. A terrestrial alternative with the coverage reduced to an estimated 95 percent of the population was considered

Disaster warning system: Satellite feasibility and comparison with terrestrial systems. Volume 2: Final report

For abstract, see Vol. 1

Self-care in primary care: findings from a longitudinal comparison study.

To examine the effects of self-care training workshops for primary healthcare workers on frequently attending patients

The self-care for people initiative: the outcome evaluation.

To determine the effects of a community-based training programme in self-care on the lay population

The Impact of Course Title and Instructor Gender on Student Perceptions and Interest in a Women's and Gender Studies Course

Diversity awareness has enormous benefits, and universities in the United States increasingly require students to complete diversity-related courses. Prior research has demonstrated that students' initial attitudes toward these courses affect their subsequent engagement, as well as the quality of their learning experience; however, very little research has examined how these initial attitudes are formed. We conducted an experiment to examine this issue in the context of a women's and gender studies course in psychology. Participants read one of two identical course descriptions that varied only the course title (i.e., Psychology of Gender versus Psychology of Women) and instructor gender. Participants perceived a women-titled course to be narrowly focused compared to an identical gender-titled course and were more interested in taking the gender-titled course. Instructor gender had no effects on any of the variables. Additionally, female participants had more positive attitudes toward the course than male participants, regardless of title. Exploratory mediation analyses indicated that the main effects of course title and participant gender were mediated by perceptions of course content. Implications for improving student experiences and interest in diversity-related courses are discussed

Vestibular evidence for the evolution of aquatic behaviour in early cetaceans

Early cetaceans evolved from terrestrial quadrupeds to obligate swimmers, a change that is traditionally studied by functional analysis of the postcranial skeleton. Here we assess the evolution of cetacean locomotor behaviour from an independent perspective by looking at the semicircular canal system, one of the main sense organs involved in neural control of locomotion. Extant cetaceans are found to be unique in that their canal arc size, corrected for body mass, is approximately three times smaller than in other mammals. This reduces the sensitivity of the canal system, most plausibly to match the fast body rotations that characterize cetacean behaviour. Eocene fossils show that the new sensory regime, incompatible with terrestrial competence, developed quickly and early in cetacean evolution, as soon as the taxa are associated with marine environments. Dedicated agile swimming of cetaceans thus appeared to have originated as a rapid and fundamental shift in locomotion rather than as the gradual transition suggested by postcranial evidence. We hypothesize that the unparalleled modification of the semicircular canal system represented a key 'point of no return' event in early cetacean evolution, leading to full independence from life on land