977 resultados para cut


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Calotrope [Calotropis procera (Aiton) W.T.Aiton] is an exotic shrub or small tree species that is currently invading the tropical savannahs of northern Australia. A chemical trial involving 11 herbicides and four application methods (foliar, basal bark, cut stump and soil applied) was undertaken to identify effective chemicals to control calotrope. Of the foliar herbicides tested, imazapyr provided 100% mortality at the rates applied, and the higher rate of metsulfuron-methyl killed 100% of the treated plants. The herbicides 2,4-D butyl ester, fluroxypyr, triclopyr and triclopyr/picloram killed greater than 80% of the plants when applied by a basal bark or cut stump (when cut 5cm above ground level) method of application. Plants cut close to ground level (5cm) were controlled more effectively than plants cut 20cm above ground level. Chemical control (foliar and cut stump spraying) is a cost effective tool to treat calotrope densities <800plants/ha. Adoption of pasture management practices that promote perennial grasses, in conjunction with strategic chemical control, would further increase the effectiveness and reduce the costs of controlling vast areas of this weed.

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Reduced supplies of nitrogen (N) in many soils of southern Queensland that were cropped exhaustively with cereals over many decades have been the focus of much research to avoid declines in profitability and sustainability of farming systems. A 45-month period of mixed grass (purple pigeon grass, Setaria incrassata Stapf; Rhodes grass, Chloris gayana Kunth.) and legume (lucerne, Medicago sativa L.; annual medics, M. scutellata L. Mill. and M. truncatula Gaertn.) pasture was one of several options that were compared at a fertility-depleted Vertosol at Warra, southern Queensland, to improve grain yields or increase grain protein concentration of subsequent wheat crops. Objectives of the study were to measure the productivity of a mixed grass and legume pasture grown over 45 months (cut and removed over 36 months) and its effects on yield and protein concentrations of the following wheat crops. Pasture production (DM t/ha) and aboveground plant N yield (kg/ha) for grass, legume (including a small amount of weeds) and total components of pasture responded linearly to total rainfall over the duration of each of 3 pastures sown in 1986, 1987 and 1988. Averaged over the 3 pastures, each 100 mm of rainfall resulted in 0.52 t/ha of grass, 0.44 t/ha of legume and 0.97 t/ha of total pasture DM, there being little variation between the 3 pastures. Aboveground plant N yield of the 3 pastures ranged from 17.2 to 20.5 kg/ha per 100 mm rainfall. Aboveground legume N in response to total rainfall was similar (10.6 - 13.2 kg/ha. 100 mm rainfall) across the 3 pastures in spite of very different populations of legumes and grasses at establishment. Aboveground grass N yield was 5.2 - 7.0 kg/ha per 100mm rainfall. In most wheat crops following pasture, wheat yields were similar to that of unfertilised wheat except in 1990 and 1994, when grain yields were significantly higher but similar to that for continuous wheat fertilised with 75 kg N/ha. In contrast, grain protein concentrations of most wheat crops following pasture responded positively, being substantially higher than unfertilised wheat but similar to that of wheat fertilised with 75 kg N/ha. Grain protein averaged over all years of assay was increased by 25 - 40% compared with that of unfertilised wheat. Stored water supplies after pasture were < 134mm (< 55% of plant available water capacity); for most assay crops water storages were 67 - 110 mm, an equivalent wet soil depth of only 0.3 - 0.45 m. Thus, the crop assays of pasture benefits were limited by low water supply to wheat crops. Moreover, the severity of common root rot in wheat crop was not reduced by pasture - wheat rotation.

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PVC-graphite polymer thick-film resistors were trimmed by a conventional air abrasive technique and the post-trim drift in resistance with time was found to be negative. The net decrease in resistance of trimmed resistors in a given time was found to be a function of resistor composition, cutting speed and temperature. Detailed studies showed this decrease to be due to a decrease in cut width with time. Two new methods, namely bombardment trimming and radiation trimming, were also tried for adjusting the resistance of these resistors and the results were compared with those obtained from abrasive trimming studies.

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Artist statement – Artisan Gallery I have a confession to make… I don’t wear a FitBit, I don’t want an Apple Watch and I don’t like bling LED’s. But, what excites me is a future where ‘wearables’ are discreet, seamless and potentially one with our body. Burgeoning E-textiles research will provide the ability to inconspicuously communicate, measure and enhance human health and well-being. Alongside this, next generation wearables arguably will not be worn on the body, but rather within the body…under the skin. ‘Under the Skin’ is a polemic piece provoking debate on the future of wearables – a place where they are not overt, not auxiliary and perhaps not apparent. Indeed, a future where wearables are under the skin or one with our apparel. And, as underwear closets the skin and is the most intimate and cloaked apparel item we wear, this work unashamedly teases dialogue to explore how wearables can transcend from the overt to the unseen. Context Wearable Technology, also referred to as wearable computing or ‘wearables’, is an embryonic field that has the potential to unsettle conventional notions as to how technology can interact, enhance and augment the human body. Wearable technology is the next-generation for ubiquitous consumer electronics and ‘Wearables’ are, in essence, miniature electronic devices that are worn by a person, under clothing, embedded within clothing/textiles, on top of clothing, or as stand-alone accessories/devices. This wearables market is predicted to grow somewhere between $30-$50 billion in the next 5 years (Credit Suisse, 2013). The global ‘wearables’ market, which is emergent in phase, has forecasted predictions for vast consumer revenue with the potential to become a significant cross-disciplinary disruptive space for designers and entrepreneurs. For Fashion, the field of wearables is arguably at the intersection of the second and third generation for design innovation: the first phase being purely decorative with aspects such as LED lighting; the second phase consisting of an array of wearable devices, such as smart watches, to communicate areas such as health and fitness, the third phase involving smart electronics that are woven into the textile to perform a vast range of functions such as body cooling, fabric colour change or garment silhouette change; and the fourth phase where wearable devices are surgically implanted under the skin to augment, transform and enhance the human body. Whilst it is acknowledged the wearable phases are neither clear-cut nor discreet in progression and design innovation can still be achieved with first generation decorative approaches, the later generation of technology that is less overt and at times ‘under the skin’ provides a uniquely rich point for design innovation where the body and technology intersect as one. With this context in mind, the wearable provocation piece ‘Under the Skin’ provides a unique opportunity for the audience to question and challenge conventional notions that wearables need to be a: manifest in nature, b: worn on or next to the body, and c: purely functional. The piece ‘Under the Skin’ is informed by advances in the market place for wearable innovation, such as: the Australian based wearable design firm Catapult with their discreet textile biometric sports tracking innovation, French based Spinali Design with their UV app based textile senor to provide sunburn alerts, as well as opportunities for design technology innovation through UNICEF’s ‘Wearables for Good’ design challenge to improve the quality of life in disadvantaged communities. Exhibition As part of Artisan’s Wearnext exhibition, the work was on public display from 25 July to 7 November 2015 and received the following media coverage: WEARNEXT ONLINE LISTINGS AND MEDIA COVERAGE: http://indulgemagazine.net/wear-next/ http://www.weekendnotes.com/wear-next-exhibition-gallery-artisan/ http://concreteplayground.com/brisbane/event/wear-next_/ http://www.nationalcraftinitiative.com.au/news_and_events/event/48/wear-next http://bneart.com/whats-on/wear-next_/ http://creativelysould.tumblr.com/post/124899079611/creative-weekend-art-edition http://www.abc.net.au/radionational/programs/breakfast/smartly-dressed-the-future-of-wearable-technology/6744374 http://couriermail.newspaperdirect.com/epaper/viewer.aspx RADIO COVERAGE http://www.abc.net.au/radionational/programs/breakfast/wear-next-exhibition-whats-next-for-wearable-technology/6745986 TELEVISION COVERAGE http://www.abc.net.au/radionational/programs/breakfast/wear-next-exhibition-whats-next-for-wearable-technology/6745986 https://au.news.yahoo.com/video/watch/29439742/how-you-could-soon-be-wearing-smart-clothes/#page1

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The four studies presented in this dissertation were designed to examine the influence of socially desirable responding (SDR) on personality research outcomes. The assessment of personality relies heavily on the use of self-report questionnaires. Their validity could be threatened by people being dishonest in their self-descriptions and ascribing more desirable traits to themselves than would be warranted by their behaviour. Scales designed to detect SDR have been around for half a century, but their status continues to be debated. Paulhus (1991) Balanced Inventory of Desirable Responding (BIDR) is perhaps the most prominent of the scales developed to distinguish between those individuals who have distorted their responses and those who have not. The first two studies included in this dissertation mostly deal with the properties of the BIDR. The other two studies are less focused on SDR scales and investigate, more generally, the potential effects of SDR on two phenomena that are of central interest to the general personality discourse personality stability over time and volunteering as participants in psychological research. The data of Studies I and II showed that Paulhus BIDR scales, designed to be indicators of SDR, are not pure measures both the communion management and self-deceptive enhancement scales are, at once, measures of response bias and measures of more substantive individual differences in behaviour. The data further suggested that the communion management and self-deceptive enhancement scales of the BIDR are somewhat accurate measures of communal and agentic bias, respectively. No evidence for a suppressor model of SDR, and only weak evidence for a moderator model, was found in those studies. Concerning research on personality stability, some data in Study I suggested that SDR may add reliable and common variance to a personality questionnaire administered at two different points in time, thus artificially inflating the test-retest correlation of that questionnaire. Furthermore, Study III demonstrated that the maturity-stability hypothesis may be in part, but not entirely, a product of SDR. Study IV suggested that some of the observed personality differences between research volunteers and nonvolunteers may be due to heightened SDR of volunteers. However, those personality differences were by no means exclusively attributable to differences in SDR. In sum, the work presented in this thesis reveals some ambiguity regarding the effects of SDR on personality research, as is true of much of the previous research on SDR. Clear-cut conclusions are difficult to reach, as the data were neither fully consistent with the view that SDR can be ignored, nor with the view that SDR needs to be controlled in some way. The struggle to understand the influence of SDR on personality research continues.

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The dispersion characteristics of Alfven surface waves along a cylindrical plasma column insulated by a neutral gas are discussed. There is no qualitative change in the characteristic curves below the critical magnetic field, given by vA approximately=s, as compared to the propagation of surface waves along the plasma-plasma interface. For magnetic fields above this critical value, there exists a cut-off wave number kc, which depends upon the azimuthal wave number, the radius of the cylinder, the strength of the magnetic field above the critical value and the gas pressure, such that surface waves do not exist for k

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We present a fast algorithm for computing a Gomory-Hu tree or cut tree for an unweighted undirected graph G = (V, E). The expected running time of our algorithm is (O) over tilde (mc) where vertical bar E vertical bar = m and c is the maximum u-v edge connectivity, where u, v is an element of V. When the input graph is also simple (i.e., it has no parallel edges), then the u-v edge connectivity for each pair of vertices u and v is at most n - 1; so the expected run-ning time of our algorithm for simple unweighted graphs is (O) over tilde (mn). All the algorithms currently known for constructing a Gomory-Hu tree [8, 9] use n - 1 minimum s-t cut (i.e., max flow) subroutines. This in conjunction with the current fastest (O) over tilde (n(20/9)) max flow algorithm due to Karger and Levine[11] yields the current best running time of (O) over tilde (n(20/9)n) for Gomory-Hu tree construction on simple unweighted graphs with m edges and n vertices. Thus we present the first (O) over tilde (mn) algorithm for constructing a Gomory-Hu tree for simple unweighted graphs. We do not use a max flow subroutine here; we present an efficient tree packing algorithm for computing Steiner edge connectivity and use this algorithm as our main subroutine. The advantage in using a tree packing algorithm for constructing a Gomory-Hu tree is that the work done in computing a minimum Steiner cut for a Steiner set S subset of V can be reused for computing a minimum Steiner cut for certain Steiner sets S' subset of S.

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A cut (A, B) (where B = V - A) in a graph G = (V, E) is called internal if and only if there exists a vertex x in A that is not adjacent to any vertex in B and there exists a vertex y is an element of B such that it is not adjacent to any vertex in A. In this paper, we present a theorem regarding the arrangement of cliques in a chordal graph with respect to its internal cuts. Our main result is that given any internal cut (A, B) in a chordal graph G, there exists a clique with kappa(G) + vertices (where kappa(G) is the vertex connectivity of G) such that it is (approximately) bisected by the cut (A, B). In fact we give a stronger result: For any internal cut (A, B) of a chordal graph, and for each i, 0 <= i <= kappa(G) + 1 such that vertical bar K-i vertical bar = kappa(G) + 1, vertical bar A boolean AND K-i vertical bar = i and vertical bar B boolean AND K-i vertical bar = kappa(G) + 1 - i. An immediate corollary of the above result is that the number of edges in any internal cut (of a chordal graph) should be Omega(k(2)), where kappa(G) = k. Prompted by this observation, we investigate the size of internal cuts in terms of the vertex connectivity of the chordal graphs. As a corollary, we show that in chordal graphs, if the edge connectivity is strictly less than the minimum degree, then the size of the mincut is at least kappa(G)(kappa(G)+1)/2 where kappa(G) denotes the vertex connectivity. In contrast, in a general graph the size of the mincut can be equal to kappa(G). This result is tight.

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The liana, hiptage (Hiptage benghalensis), is currently invading the wet tropics of northern Queensland and remnant bushland in south-eastern Queensland, Australia. Trials using seven herbicides and three application methods (foliar, basal bark, and cut stump) were undertaken at a site in north Queensland (158 700 hiptage plants ha−1). The foliar-applied herbicides were only effective in controlling the hiptage seedlings. Of the foliar herbicides trialed, dicamba, fluroxypyr, and triclopyr/picloram controlled >75% of the treated seedlings. On the larger plants, the cut stump applications were more effective than the basal bark treatments. Kills of >95% were obtained when the plants were cut close to ground level (5 cm) and treated with herbicides that were mixed with diesel (fluroxypyr and triclopyr/picloram), with water (glyphosate), or were applied neat (picloram). The costings for the cut stump treatment of a hiptage infestation (85 000 plants ha−1), excluding labor, would be $A14 324 ha−1 using picloram and $A5294 ha−1 and $A2676 ha−1, respectively, using glyphosate and fluroxypyr. Foliar application using dicamba for seedling control would cost $A1830 ha−1. The costs range from 2–17 cents per plant depending on the treatment. A lack of hiptage seeds below the soil surface, a high germinability (>98%) of the viable seeds, a low viability (0%) of 2 year old, laboratory-stored fruit, and a seedling density of 0.1 seedlings m−2 12 months after a control program indicate that hiptage might have a short-term seed bank. Protracted recolonization from the seed bank would therefore be unlikely after established seed-producing plants have been controlled.

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Koster´s curse is a highly invasive, perennial shrub with potential to become a major weed in many parts of Queensland and elsewhere in Australia. Presently, there is one infestation discovered in Australia and the species is a Class 1 weed. It grows to 5 m and can produce over 500 berries annually which are dispersed by birds and water. This study quantified growth and the effects of damage on survival and time to reproduction under both field and shade house conditions in the Wet Tropics of north Queensland. Plants recovered to their original size and were capable of setting seed in as few as 86 days and 194 days after being cut back to 10 cm and 0 cm respectively.

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Prickly acacia, Acacia nilotica subsp. indica (Benth.) Brenan, a major weed of the Mitchell Grass Downs of northern Queensland, Australia, has been the target of biological control projects since the 1980s. The leaf-feeding caterpillar Cometaster pyrula (Hopffer) was collected from Acacia nilotica subsp. kraussiana (Benth.) Brenan during surveys in South Africa to find suitable biological control agents, recognised as a potential agent, and shipped into a quarantine facility in Australia. Cometaster pyrula has a life cycle of approximately 2 months during which time the larvae feed voraciously and reach 6 cm in length. Female moths oviposit a mean of 339 eggs. When presented with cut foliage of 77 plant species, unfed neonates survived for 7 days on only Acacia nilotica subsp. indica and Acacia nilotica subsp. kraussiana. When unfed neonates were placed on potted plants of 14 plant species, all larvae except those on Acacia nilotica subsp. indica and Acacia nilotica subsp. kraussiana died within 10 days of placement. Cometaster pyrula was considered to be highly host specific and safe to release in Australia. Permission to release C. pyrula in Australia was obtained and the insect was first released in north Queensland in October 2004. The ecoclimatic model CLIMEX indicated that coastal Queensland was climatically suitable for this insect but that inland areas were only marginally suitable.

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A replicated trial was conducted at Tallegalla in south-east Queensland to assess the effectiveness of a range of control methods for climbing asparagus Asparagus africanus Lam. A total of 18 treatments using mechanical, cut stump, basal bark, foliar spray and splatter gun techniques were trialled with a range of herbicides and application rates. Removing the plant and placing it above the ground surface was most effective in killing climbing asparagus. Basal bark spraying of 24 g triclopyr ester (40 mL Garlon® 600) or 10 g fluroxypyr ester (50 mL Starane® 200) L-1 diesel and the cut stump application of neat diesel or 225 g glyphosate (500 mL Glyphosate CT®) L-1 water offered the best chemical control of climbing asparagus.

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The geometrid caterpillar Isturgia deerraria was imported from Kenya into quarantine facilities in Australia as a potential biological control agent for prickly acacia, Acacia nilotica subsp. indica (Benth.) Brenan (family Mimosaceae). The insect was then tested on 30 plant species presented to neonate larvae as a no-choice cut foliage test and 13 plant species presented as a no-choice potted plant test. In these tests the insect was able to complete its life cycle on 13 native Acacia spp. and also on Acacia farnesiana and the exotic ornamental Delonix regia (family Caesalpiniaceae). The tests supported field observations that the insect has a host range spanning many leguminous species and as such the insect could not be considered for release in Australia.

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The properties of Co4Sb12 with various In additions were studied. X-ray diffraction revealed the presence of the pure δ-phase of In0.16Co4Sb12, whereas impurity phases (γ-CoSb2 and InSb) appeared for x = 0.25, 0.40, 0.80, and 1.20. The homogeneity and morphology of the samples were observed by Seebeck microprobe and scanning electron microscopy, respectively. All the quenched ingots from which the studied samples were cut were inhomogeneous in the axial direction. The temperature dependence of the Seebeck coefficient (S), electrical conductivity (σ), and thermal conductivity (κ) was measured from room temperature up to 673 K. The Seebeck coefficient of all In-added Co4Sb12 materials was negative. When the filler concentration increases, the Seebeck coefficient decreases. The samples with In additions above the filling limit (x = 0.22) show an even lower Seebeck coefficient due to the formation of secondary phases: InSb and CoSb2. The temperature variation of the electrical conductivity is semiconductor-like. The thermal conductivity of all the samples decreases with temperature. The central region of the In0.4Co4Sb12 ingot shows the lowest thermal conductivity, probably due to the combined effect of (a) rattling due to maximum filling and (b) the presence of a small amount of fine-dispersed secondary phases at the grain boundaries. Thus, regardless of the non-single-phase morphology, a promising ZT (S 2 σT/κ) value of 0.96 at 673 K has been obtained with an In addition above the filling limit.