2,768 research outputs found
Polymer multimode waveguide optical and electronic PCB manufacturing
No full textThe paper describes the research in the £1.3 million IeMRC Integrated Optical and Electronic Interconnect PCB Manufacturing (OPCB) Flagship Project in which 8 companies and 3 universities carry out collaborative research and which was formed and is technically led by the author. The consortium’s research is aimed at investigating a range of fabrication techniques, some established and some novel, for fabricating polymer multimode waveguides from several polymers, some formulations of which are being developed within the project. The challenge is to develop low cost waveguide manufacturing techniques compatible with commercial PCB manufacturing and to reduce their alignment cost. The project aims to take the first steps in making this hybrid optical waveguide and electrical copper track printed circuit board disruptive technology widely available by establishing and incorporating waveguide design rules into commercial PCB layout software and transferring the technology for fabricating such boards to a commercial PCB manufacturer. To focus the research the project is designing an optical waveguide backplane to tight realistic constraints, using commercial layout software with the new optical design rules, for a demonstrator into which 4 daughter cards are plugged, each carrying an aggregate of 80 Gb/s data so that each waveguide carries 10 Gb/s
The Chance and Probability Concepts Project
No full textThis article, created by D.R. Green, describes an investigation of what concepts and intuitions concerning random processes are present in the minds of children of varying abilities across the 11-16 age range. The ability to list permutations, combinations and arrangements is also being investigated. The author states, "Over the past two decades the topic of 'Probabilityâ has been brought into the mathematics curriculum but it may be that this is more an empty gesture rather than a sound strategy." This article can help to alleviate many of the struggles in teaching probability concepts. The article is pitched at a more elementary audience, but is still a perfect resource for almost anyone teaching in the field
Achieving 10 ps coincidence time resolution in TOF-PET is an impossible dream
No full textGreen Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.RST/Radiation, Science and TechnologyRST/Medical Physics & Technolog
Bepalen van het massatraagheidsmoment met behulp van een bifilar pendulum: Determining the moments of inertia using a bifilar pendulum
No full textThe aim of this thesis is to investigate the use of a bifilar pendulum for determining the moments of inertia of the TU Delft solar boat and to quantitatively predict the estimates. In the first part, several methods are discussed which can be applied in deriving the equations of motion of the pendulum. A new method, Kane's method, will be introduced. In the second part, this method will be used to derive the actual equations of motion. These equations are linearized around of the the pendulum's stationary positions to obtain expressions which link the moment of inertia about an axis to the period of oscillation of the pendulum about that axis. These equations are subsequently applied to the solar boat to derive estimates for the moments of inertia about the principle axis of the boat. The results of this thesis considers three different configurations of the bifilar pendulum with the solar boat suspended. One of these configurations results in the most accurate estimates for the moments of inertia, however, these have not been quantitatively predicted. The author suggests a modification in the definition of the bifilar pendulum such that this might be possible.Electrical Engineering, Mathematics and Computer ScienceNumerical analysi
An introduction to management science: quantitative approaches to decision making
No full textRetaining the accessible application-driven approach for which An Introduction to Management Science is highly regarded, adapting author Mik Wisniewski has carefully reworked the existing US textbook to benefit students across the UK, Europe, Middle East and Africa. Packed with diverse realistic examples from Scotland to Saudi Arabia, the landmark text from the ASW team is now available in a truly internationalised version for students studying Management Science and Operations Research at postgraduate and undergraduate level
Immunotherapy
No full textA chapter covering metastasis immunotherapy in multi-author volume devoted to all aspects of cancer metastasis
Olfactory responses of the omnivorous generalist predator Dicyphus hesperusto plant and prey odours
No full textResponses of female Dicyphus hesperus Knight (Heteroptera: Miridae) to the odours of plants and prey were tested in the laboratory using a Y-tube olfactometer. Females were attracted to the odour of tomato leaves infested with nymphs of the greenhouse whitefly, Trialeurodes vaporariorum Westwood (Homoptera: Aleyrodidae), compared to uninfested leaves. No such attraction occurred to tomato leaves infested with two-spotted spider mites, Tetranychus urticae Koch (Acari: Tetranychidae). When females were simultaneously presented with the odours of whitefly and mite-infested leaves, no preference for either odour was recorded. Similarly, females were attracted to the odour of pepper leaves infested with green peach aphids [Myzus persicae (Sulzer) (Homoptera: Aphididae)] compared to uninfested leaves, but were not attracted to the odour of pepper leaves infested with eggs of cabbage loopers, Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae). When aphid-infested and looper-egg-infested pepper leaves were presented simultaneously, no preference for either odour was detected. The results are discussed as they relate to the evolution of infochemical use in generalist omnivorous predators. [ABSTRACT FROM AUTHOR]Peer reviewedfinal article publishedTrialeurodes vaporariorumMiridaeHeteropterabiological controlpeppertomatoTrichoplusia niMyzus persicaeTetranychus urtica
Broken-formations of the Pulaski thrust sheet near Pulaski, Virginia
No full textBroken-formations (Hsu, 1974; Harris and Milici, 1977) occur in the lower part of the Pulaski thrust sheet and contain some of the most strongly deformed sedimentary rocks in the Valley and Ridge province of the southern Appalachians. Deformation in this zone ranges from grain-scale cataclasis to regional-scale faulting. The broken-formations are distinguished from rocks structurally higher on the sheet and from rocks of the underlying Saltville sheet by (1) a sharp increase in the variability of fold and fault styles, (2) greater ranges in fold plunges and dips of axial surfaces, (3) a low degree of preferred orientation of folds and faults, (4) an increase in the frequency of mesoscopic structures, and (5) the presence of Max Meadows tectonic breccia. Structural analyses indicate that deformation in the broken-formations is Alleghanian in age and that the deformed zone formed under elastico-frictional conditions, possibly under elevated fluid pressures with temporally variant stresses and that lithology may have played an important role in localizing the broken-formations along the base of the Pulaski sheet.Ph. D
Prey feeding increases water stress in the omnivorous predator Dicyphus hesperus
No full textThe effects of water stress (produced by water deprivation and prey feeding) on plant feeding were investigated in the omnivorous predator Dicyphus hesperus Knight (Hemiptera: Miridae). The objective was to determine if prey feeding aggravated water deficits and thus increased plant feeding. We measured plant feeding in a factorial experiment where female D. hesperus were prepared for experiments by providing or withholding water and/or prey for 24 h. We then evaluated the amount of plant feeding on Nicotiana tabacum seedlings by the direct observation of insects at three different densities of the prey, Ephestia kuehniella eggs. The amount of plant feeding, as measured by frequency of plant feeding bouts and time spent plant feeding during observation, was significantly greater for water-deprived individuals than for those that had been provided with water. Individuals that had been provided with prey fed on plants at a significantly higher frequency than prey-deprived individuals at two of the prey densities used in the experiment. These results support the hypothesis that plant feeding in zoophytophagous Hemiptera facilitates prey feeding by providing water that is essential for predation. [ABSTRACT FROM AUTHOR]Peer reviewedFinal article publishedMiridaezoophytophagous predatortomatoplant feedingomnivorygeneralist predatorDicyphus hesperusbiological controlHeteropter
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Atomic collision databases and data services -- A survey
No full textAtomic collision databases and data services constitute an important resource for scientific and engineering applications such as astrophysics, lighting, materials processing, and fusion energy, as well as an important knowledge base for current developments in atomic collision physics. Data centers and research groups provide these resources through a chain of efforts that include producing and collecting primary data, performing evaluation of the existing data, deducing scaling laws and semiempirical formulas to compactly describe and extend the data, producing the recommended sets of data, and providing convenient means of maintaining, updating, and disseminating the results of this process. The latest efforts have utilized modern database, storage, and distribution technologies including the Internet and World Wide Web. Given here is an informal survey of how these resources have developed, how they are currently characterized, and what their likely evolution will lead them to become in the future
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