9,569 research outputs found

    Improving sustainability through intelligent cargo and adaptive decision making

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    In the current society, logistics is faced with the challenge to meet more stringent sustainability goals. Shippers and transport service providers both aim to reduce the carbon footprint of their logistic operations. To do so, optimal use of logistics resources and physical infrastructure should be aimed for. An adaptive decision making process for the selection of a specific transport modality, transport provider and timeslot (aimed at minimisation of the carbon footprint) enables shippers to achieve this. This requires shippers to have access to up-to-date capacity information from transport providers (e.g. current and scheduled loading status of the various transport means and information on carbon footprint) and traffic information (e.g. city logistics and current traffic information). A prerequisite is an adequate infrastructure for collaboration and open exchange of information between the various stakeholders in the logistics value chain to obtain the up-to-date information. This paper gives a view on how such an advanced information infrastructure can be realised, currently being developed within the EU iCargo project. The paper describes a reference logistics value chain, including business benefits for each of the roles in the logistics value chain of aiming for sustainability. A case analysis is presented that reflects a practical situation in which the various roles collaborate and exchange information for realizing sustainability goals, using adaptive decision making for selecting a transport modality, transport provider, and timeslot. A high-level overview is provided of the requirements on and technical implementation of the supporting advanced infrastructure for collaboration and open information exchange.In the current society, logistics is faced with the challenge to meet more stringent sustainability goals. Shippers and transport service providers both aim to reduce the carbon footprint of their logistic operations. To do so, optimal use of logistics resources and physical infrastructure should be aimed for. An adaptive decision making process for the selection of a specific transport modality, transport provider and timeslot (aimed at minimisation of the carbon footprint) enables shippers to achieve this. This requires shippers to have access to up-to-date capacity information from transport providers (e.g. current and scheduled loading status of the various transport means and information on carbon footprint) and traffic information (e.g. city logistics and current traffic information). A prerequisite is an adequate infrastructure for collaboration and open exchange of information between the various stakeholders in the logistics value chain to obtain the up-to-date information. This paper gives a view on how such an advanced information infrastructure can be realised, currently being developed within the EU iCargo project. The paper describes a reference logistics value chain, including business benefits for each of the roles in the logistics value chain of aiming for sustainability. A case analysis is presented that reflects a practical situation in which the various roles collaborate and exchange information for realizing sustainability goals, using adaptive decision making for selecting a transport modality, transport provider, and timeslot. A high-level overview is provided of the requirements on and technical implementation of the supporting advanced infrastructure for collaboration and open information exchange.In the current society, logistics is faced with the challenge to meet more stringent sustainability goals. Shippers and transport service providers both aim to reduce the carbon footprint of their logistic operations. To do so, optimal use of logistics resources and physical infrastructure should be aimed for. An adaptive decision making process for the selection of a specific transport modality, transport provider and timeslot (aimed at minimisation of the carbon footprint) enables shippers to achieve this. This requires shippers to have access to up-to-date capacity information from transport providers (e.g. current and scheduled loading status of the various transport means and information on carbon footprint) and traffic information (e.g. city logistics and current traffic information). A prerequisite is an adequate infrastructure for collaboration and open exchange of information between the various stakeholders in the logistics value chain to obtain the up-to-date information. This paper gives a view on how such an advanced information infrastructure can be realised, currently being developed within the EU iCargo project. The paper describes a reference logistics value chain, including business benefits for each of the roles in the logistics value chain of aiming for sustainability. A case analysis is presented that reflects a practical situation in which the various roles collaborate and exchange information for realizing sustainability goals, using adaptive decision making for selecting a transport modality, transport provider, and timeslot. A high-level overview is provided of the requirements on and technical implementation of the supporting advanced infrastructure for collaboration and open information exchange

    On Central Charges and Hamiltonians for 0-brane dynamics

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    We consider general properties of central charges of zero branes and associated duality invariants, in view of their double role, on the bulk and on the world volume (quantum-mechanical) theory. A detailed study of the BPS condition for the mass spectrum arising from toroidal compactifications is given for 1/2, 1/4 and 1/8 BPS states in any dimensions. As a byproduct, we retreive the U-duality invariant conditions on the charge (zero mode) spectrum and the orbit classification of BPS states preserving different fractions of supersymmetry. The BPS condition for 0-branes in theories with 16 supersymmetries in any dimension is also discussed.Comment: 23 pages, latex fil

    Proposal of a topological M(atrix) theory

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    Keeping in mind the several models of M(atrix) theory we attempt to understand the possible structure of the topological M(atrix) theory ``underlying'' these approaches. In particular we are motivated by the issue about the nature of the structure of the vacuum of the topological M(atrix) theory and how this could be related to the vacuum of the electroweak theory. In doing so we are led to a simple topological matrix model. Moreover it is intuitively expected from the current understanding that the noncommutative nature of ``spacetime'' and background independence should lead to a topological Model. The main purpose of this note is to propose a simple topological Matrix Model which bears relation to F and M theories. Suggestions on the origin of the chemical potential term appearing in the matrix models are given.Comment: 14 pages revte

    Open membranes, ribbons and deformed Schild strings

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    We analyze open membranes immersed in a magnetic three-form field-strength CC. While cylindrical membranes in the absence of CC behave like tensionless strings, when the CC flux is present the strings polarize into thin membrane ribbons, locally orthogonal to the momentum density, thus providing the strings with an effective tension. The effective dynamics of the ribbons can be described by a simple deformation of the Schild action for null strings. Interactions become non-local due to the polarization, and lead to a deformation of the string field theory, whereby string vertices receive a phase factor proportional to the volume swept out by the ribbons. In a particular limit, this reduces to the non-commutative loop space found previously.Comment: revte

    Reducing the sodium content of high-salt foods: Effect on cardiovascular disease in South Africa

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    Background. Average salt intake in South African (SA) adults, 8.1 g/day, is higher than the 4 - 6 g/day recommended by the World Health Organization. Much salt consumption arises from non-discretionary intake (the highest proportion from bread, with contributions from margarine, soup mixes and gravies). This contributes to an increasing burden of hypertension and cardiovascular disease (CVD).Objectives. To provide SA-specific information on the number of fatal CVD events (stroke, ischaemic heart disease and hypertensive heart disease) and non-fatal strokes that would be prevented each year following a reduction in the sodium content of bread, soup mix, seasoning and margarine.Methods. Based on the potential sodium reduction in selected products, we calculated the expected change in population-level systolic blood pressure (SBP) and mortality due to CVD and stroke.Results. Proposed reductions would decrease the average salt intake by 0.85 g/person/day. This would result in 7 400 fewer CVD deaths and 4 300 less non-fatal strokes per year compared with 2008. Cost savings of up to R300 million would also occur.Conclusion. Population-wide strategies have great potential to achieve public health gains as they do not rely on individual behaviour or a well-functioning health system. This is the first study to show the potential effect of a salt reduction policy on health in SA

    Elastic scattering of low energy pions by nuclei and the in-medium isovector pi N amplitude

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    Measurements of elastic scattering of 21.5 MeV pi+ and pi- by Si, Ca, Ni and Zr were made using a single arm magnetic spectrometer. Absolute calibration was made by parallel measurements of Coulomb scattering of muons. Parameters of a pion-nucleus optical potential were obtained from fits to all eight angular distributions put together. The `anomalous' s-wave repulsion known from pionic atoms is clearly observed and could be removed by introducing a chiral-motivated density dependence of the isovector scattering amplitude, which also greatly improved the fits to the data. The empirical energy dependence of the isoscalar amplitude also improves the fits to the data but, contrary to what is found with pionic atoms, on its own is incapable of removing the anomaly.Comment: 20 pages, 5 figures, 5 tables. V2 added details on uncertainties,extended discussion. To appear in PR

    Canonical Quantization of Open String and Noncommutative Geometry

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    We perform canonical quantization of open strings in the DD-brane background with a BB-field. Treating the mixed boundary condition as a primary constraint, we get a set of secondary constraints. Then these constraints are shown to be equivalent to orbifold conditions to be imposed on normal string modes. These orbifold conditions are a generalization of the familiar orbifold conditions which arise when we describe open strings in terms of closed strings. Solving the constraints explicitly, we obtain a simple Hamiltonian for the open string, which reveals the nature of noncommutativity transparently.Comment: 14 pages, RevTex, added reference

    The Spectral Curve of the Lens Space Matrix Model

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    Following hep-th/0211098 we study the matrix model which describes the topological A-model on T^{*}(S^{3}/\ZZ_p). We show that the resolvent has square root branch cuts and it follows that this is a p cut single matrix model. We solve for the resolvent and find the spectral curve. We comment on how this is related to large N transitions and mirror symmetry.Comment: 25 pages, 2 figures, typos corrected, comments adde

    Histologic and bacteriologic findings in valvular endocarditis of slaughter-age pigs

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    Endocarditis lesions from 117 slaughter pigs were examined pathologically and etiologically in addition to 90 control hearts with cardiac valves. Lesions were located on the valves; however, the lesions had extended to the walls in 21 cases (18%). Lesions predominated on the mitral valve (59%). A total of 28 cases, from which no growth was obtained or a contamination flora was grown, were screened by fluorescence in situ hybridization (FISH) for bacteria (general bacterial probe) and probes specific for Streptococcus suis and Erysipelothrix rhusiopathiae, respectively. Using FISH, an additional 10 cases of endocarditis due to S. suis and E. rhusiopathiae were disclosed. Within lesions, streptococci predominated (53%) followed by E. rhusiopathiae (30%). Distinct features of both the lesions and the shape and localization of bacterial colonies were related to streptococci and E. rhusiopathiae. The propensity for streptococci to be localized on more than 1 valve in single hearts may be because S. suis–infected pigs tend to have been infected for a longer period compared with E. rhusiopathiae. Mineralization of endocarditis lesions was significantly associated with infection by streptococci, and was seen in 71% of the cases, whereas it was present in only 28% of lesions caused by E. rhusiopathiae. In addition, areas with mineralization were significantly correlated to the presence of a granulomatous reaction. Granulomatous endocarditis is likely a result of a foreign body reaction due to dystrophic mineralization. Local proliferation of valvular endothelial cells, found in 9 hearts in the current study, may increase the risk of developing thrombosing endocarditis in pigs. </jats:p
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