3,956 research outputs found

    Hidden innovation in the construction and property sectors

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    The construction and property industries have a poor reputation for innovation. Indeed, this reputation appears to be backed by official statistics which projects these industries as being devoid of innovative activity. However, the reputation is undeserved. Official statistics misrepresent the extent and nature of innovation in these sectors. A closer analysis reveals that much of the innovation that exists in the sector is hidden from conventional measures. By its nature therefore, it is difficult to measure the precise extent of this innovation and disaggregate it from general improvement. This opaqueness strengthens the need for policymakers, practitioners and researchers within, amongst others, the surveying sector to go beyond the visible spectrum of innovation and design and implement appropriate policies, knowledge bases and practices which engage and leverage the hitherto hidden aspects of innovation

    Action learning as an enabler for successful technology transfer with construction SMEs

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    There is an increasing demand for construction companies to adopt and use new technologies. At the same time universities are increasingly being called upon to assist with ‘technology transfer’ through positive engagement with industry. However, there is little literature investigating technology transfer from the perspective of small construction companies which make up the overwhelming majority of firms in the sector. This paper contributes to this developing area by providing a literature review of technology transfer and proposing a holistic system required for success. Building upon this review it assesses the potential use of action learning as a means of providing this holistic solution and, in so doing, promoting technology transfer and improving the links between higher education institutions (HEIs) and the construction industry. The assessment is made through a literature review of action learning in construction and an analysis of results from the national Construction Knowledge Exchange (CKE) initiative which uses an action learning methodology to assist HEIs in supporting local construction small and medium-sized enterprises (SMEs). The initial results show that this innovative approach, has been successful in creating synergies between academic and business worlds, helping HEIs to communicate more effectively with businesses and vice versa. However, the results indicate that innovations which small construction companies tend to more successfully adopt are those which can contribute to the business in a quick, tangible fashion, and which can be dovetailed into existing rganisational capabilities. This is found to be in marked contrast to the relevant literature which depict large companies operating in more complex networks, drawing upon them for new tacit and explicit technologies which support more long term, formal technology strategies, and which often complement some form of specialised internal research and development capability. The implication for policy is that any technology transfer initiatives need to appreciate and actively manage the different motivations and capabilities of small and large construction companies to absorb and use new technology

    The vanishing ideal of a finite set of points with multiplicity structures

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    Given a finite set of arbitrarily distributed points in affine space with arbitrary multiplicity structures, we present an algorithm to compute the reduced Groebner basis of the vanishing ideal under the lexicographic ordering. Our method discloses the essential geometric connection between the relative position of the points with multiplicity structures and the quotient basis of the vanishing ideal, so we will explicitly know the set of leading terms of elements of I. We split the problem into several smaller ones which can be solved by induction over variables and then use our new algorithm for intersection of ideals to compute the result of the original problem. The new algorithm for intersection of ideals is mainly based on the Extended Euclidean Algorithm.Comment: 12 pages,12 figures,ASCM 201

    Non-Abelian discrete gauge symmetries in 4d string models

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    We study the realization of non-Abelian discrete gauge symmetries in 4d field theory and string theory compactifications. The underlying structure generalizes the Abelian case, and follows from the interplay between gaugings of non-Abelian isometries of the scalar manifold and field identifications making axion-like fields periodic. We present several classes of string constructions realizing non-Abelian discrete gauge symmetries. In particular, compactifications with torsion homology classes, where non-Abelianity arises microscopically from the Hanany-Witten effect, or compactifications with non-Abelian discrete isometry groups, like twisted tori. We finally focus on the more interesting case of magnetized branes in toroidal compactifications and quotients thereof (and their heterotic and intersecting duals), in which the non-Abelian discrete gauge symmetries imply powerful selection rules for Yukawa couplings of charged matter fields. In particular, in MSSM-like models they correspond to discrete flavour symmetries constraining the quark and lepton mass matrices, as we show in specific examples.Comment: 58 pages; minor typos corrected and references adde

    On the spectral problem of N=4 SYM with orthogonal or symplectic gauge group

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    We study the spectral problem of N=4 SYM with gauge group SO(N) and Sp(N). At the planar level, the difference to the case of gauge group SU(N) is only due to certain states being projected out, however at the non-planar level novel effects appear: While 1/N-corrections in the SU(N) case are always associated with splitting and joining of spin chains, this is not so for SO(N) and Sp(N). Here the leading 1/N-corrections, which are due to non-orientable Feynman diagrams in the field theory, originate from a term in the dilatation operator which acts inside a single spin chain. This makes it possible to test for integrability of the leading 1/N-corrections by standard (Bethe ansatz) means and we carry out various such tests. For orthogonal and symplectic gauge group the dual string theory lives on the orientifold AdS5xRP5. We discuss various issues related to semi-classical strings on this background.Comment: 25 pages, 3 figures. v2: Minor clarifications, section 5 expande

    Heavy Flavour Production at Tevatron and Parton Shower Effects

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    We present hadron-level predictions from the Monte Carlo generator Cascade and numerical calculations of charm and beauty production at the Fermilab Tevatron within the framework of the kTk_T-factorization QCD approach. Our consideration is based on the CCFM-evolved unintegrated gluon densities in a proton. The performed analysis covers the total and differential cross sections of open charm and beauty quarks, BB and DD mesons (or rather muons from their semileptonic decays) and the total and differential cross sections of bbˉb \bar b di-jet hadroproduction. We study the theoretical uncertainties of our calculations and investigate the effects coming from parton showers in initial and final states. Our predictions are compared with the recent experimental data taken by the D0 and CDF collaborations. Special attention is put on the specific angular correlations between the final-state particles. We demonstrate that the final state parton shower plays a crucial role in the description of such observables. The decorrelated part of angular separations can be fully described, if the process gg∗→gggg^*\rightarrow gg is included.Comment: Fig 8,9 10 replaced, small corrections in text A discussion of the delta phi results is adde

    Gravitational Wave Detection by Interferometry (Ground and Space)

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    Significant progress has been made in recent years on the development of gravitational wave detectors. Sources such as coalescing compact binary systems, neutron stars in low-mass X-ray binaries, stellar collapses and pulsars are all possible candidates for detection. The most promising design of gravitational wave detector uses test masses a long distance apart and freely suspended as pendulums on Earth or in drag-free craft in space. The main theme of this review is a discussion of the mechanical and optical principles used in the various long baseline systems in operation around the world - LIGO (USA), Virgo (Italy/France), TAMA300 and LCGT (Japan), and GEO600 (Germany/U.K.) - and in LISA, a proposed space-borne interferometer. A review of recent science runs from the current generation of ground-based detectors will be discussed, in addition to highlighting the astrophysical results gained thus far. Looking to the future, the major upgrades to LIGO (Advanced LIGO), Virgo (Advanced Virgo), LCGT and GEO600 (GEO-HF) will be completed over the coming years, which will create a network of detectors with significantly improved sensitivity required to detect gravitational waves. Beyond this, the concept and design of possible future "third generation" gravitational wave detectors, such as the Einstein Telescope (ET), will be discussed.Comment: Published in Living Reviews in Relativit

    Physics, Astrophysics and Cosmology with Gravitational Waves

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    Gravitational wave detectors are already operating at interesting sensitivity levels, and they have an upgrade path that should result in secure detections by 2014. We review the physics of gravitational waves, how they interact with detectors (bars and interferometers), and how these detectors operate. We study the most likely sources of gravitational waves and review the data analysis methods that are used to extract their signals from detector noise. Then we consider the consequences of gravitational wave detections and observations for physics, astrophysics, and cosmology.Comment: 137 pages, 16 figures, Published version <http://www.livingreviews.org/lrr-2009-2
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