1,736,214 research outputs found
General morphology, classification and biology of Cerambycidae
Full text linkSingle chapter permitted OA by publisher.Cerambycids as economic pests are not only important with respect to forest trees but also for various agricultural and horticultural crops. Damage to crops is usually caused by larval feeding and, occasionally, by adult feeding or oviposition. Larvae of most cerambycid species are borers, feeding on living, dying, dead, or rotten plant stems, branches, or twigs. Most wood-boring species feed on subcortical tissues-at least initially. Later, they may burrow further into sapwood and-even hardwood-to continue feeding. Herbaceous feeders usually bore in host stems. Root feeders may bore in the roots, hollowing out and killing the roots of the host plants, or they may live in the soil and feed on the roots. In some species, larvae damage fruit; adults cause economic damage to leaves and male owers by feeding and to stems or branches by girdling.falseUS
On the Role of the Kuroshio Extension Bimodality in Modulating the Surface Eddy Kinetic Energy Seasonal Variability
No full textThe modulation of the seasonal variability of the surface eddy kinetic energy (EKE) in the Kuroshio extension (KE) region induced by the stable and unstable KE states is analyzed using satellite-based observations and high-resolution ocean reanalysis data. The two KE states are found to strongly modulate the seasonal variability of the local surface EKE: the latter reaches its maximum in May–July if the KE is in its stable state, while it peaks in August–October if the KE is in its unstable state. Further investigation indicates that such behavior is mainly caused by the different baroclinic energy transfers induced by the meridional density gradients associated with the two KE states
Symptotic theory for zero energy density estimation with nonparametric regression applications
No full textThe effect of nano size fillers on electrical performance of epoxy resin
No full textEpoxy resin is widely used in high voltage apparatus as insulation due to its excellent mechanical, electrical and chemical properties. Fillers are often added to epoxy resin to enhance its mechanical, thermal and chemical properties. With the new development in nanotechnology, it has been widely anticipated that the combination of nanoparticles with traditional resin systems may create nanocomposite materials with enhanced electrical, thermal and mechanical properties. The project aims to improve the overall electrical performance by adding nanoparticles into epoxy resin. In the present thesis a detailed study on dielectric permittivity, AC breakdown strength and space charge behaviour of epoxy resin/nanocomposites with nano-fillers of SiO2 and Al2O3 has been carried out. The epoxy resin/nanocomposite thin film samples were prepared and tests were carried out to measure their dielectric permittivity and tan delta value in frequency range of 1Hz- 1MHz. The space charge behaviours were also observed by using the pulse electroacoustic (PEA) technique. The influence of filler type, filler size and filler concentration on nanocomposites ac breakdown strength were also examined. In addition, traditional epoxy resin microcomposites were also prepared and tested and the results were compared with those obtained from epoxy resin/nanocomposites. The present results indicate that the presence of nano-sized fillers enhances the insulation properties of the epoxy resin and the dielectric properties are strongly influenced by the interfacial region between epoxy and nano particles. It is the key factor that affects the electrical performance of epoxy nanocomposites. The multi core model has been applied to explain the effects of such interfacial region on the electrical performance epoxy nanocomposites. A new phenomenon of space charge accumulation at higher nano size filler loading concentration has been observed at a filler loading concentration above 3wt%. This phenomenon is a result of the formation of electrical double layer surrounding the nano particles. A comparison study between epoxy nanocomposites loaded with both surface treated and non-surface treated nano particles has also been carried out. The results indicate that nano particle dispersion rate is an important factor in determine the electrical performance epoxy nanocomposites. Surface functionalisation on nano size fillers by using silane as a coupling agent could help avoiding the formation of large agglomerations resulting in better insulating performance. In addition, it has also been found that the presence of water inside epoxy nanocomposites also leads to the reduction in dielectric properties due to the formation of water layers surrounding the nano particles. Those water layers could act as a conductive path to help charge carriers travelling through the bulk of the materials
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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