1,051 research outputs found
A QCD sum rules calculation of the strong coupling constant
In this work, we calculate the form factors and the coupling constant of the
strange-charmed vertex in the framework of the QCD sum rules
by studying their three-point correlation functions. All the possible off-shell
cases are considered, , and , resulting in three different
form factors. These form factors are extrapolated to the pole of their
respective off-shell mesons, giving the same coupling constant for the process.
Our final result for the coupling constant is .Comment: 17 pages, 4 figure
Evaluation of fruit and seed diversity and characterization of carob (Ceratonia siliqua L.) cultivars in Algarve region
The genetic diversity of 15 carob (
Ceratonia siliqua
L.) cultivars located in an experimental field from Algarve (Portugal) was evaluated over 7
years using 12 fruit and seed phenotypic characters, in order to characterize carob cultivars. The values of morphological traits obtained by cultiv
ar
were compared with those from other countries of the Mediterranean basin. Statistically significant differences were found between cultivars for al
l
characters which were examined, what indicates a high genetic diversity. The relationship among these characters was analyzed by principal
component analysis (PCA) resulting in the separation of these cultivars classed in four groups (clusters I–IV) and in four ungrouped cultivars. A
three dimension of the model was found to be significant and explained 74.5% of the total variation, in which the first component accounting for
34.6% of the total variation is dominated by fruit characters, while the second component is dominated by seed characters. Cultivars plotted on the
left-lower quadrant on the space determined by principal components 1 and 2 are characterized by fruits with high seed yield more appropriated for
industrial rentability. The correlation analyses established by cultivar provided a specific understanding about the way how fruit and seed
characteristics correlate within each cultivar. This approach can be useful for the development of a breeding programme, aiming to increase the
seed yield, seed thickness, individual and total seed weight by fruit, characteristics that are determinant to improve the industrial exploitation
of carob
Interaction with a kinetic folded surface
Kinetic systems offers new perspectives and design innovation in research and
practice. These systems have been used by architects as an approach that embeds
computation intelligence to create flexible and adaptable architectural spaces
according to users changing needs and desires as a way to respond to an
increasingly technological society. The presented research attempts to answer to
this question based on the results of a multidisciplinary on-going work developed
at digital fabrication laboratory Vitruvius Fablab-IUL in Lisbon. The main goal
is to explore the transformation of the shape of a construction by mechanisms
which allow adaptation either to environmental conditions or to the needs of the
user. This paper reports the initial development of a kinetic system based on an
origami foldable surface actuated by a user. The user can manipulate a small
scale model of the surface and evaluate at all times if it is achieving the desired
geometryinfo:eu-repo/semantics/publishedVersio
Kinetic origami surfaces: from simulation to fabrication
On nowadays social, technological and economic context everything changes constantly so there is the persistent need to adapt at all levels. This research defends that Architecture should do the same through the use of kinetic and interactive buildings, or elements in a building. These elements should allow the building to adapt to changing needs and conditions. This article describes the current state of an ongoing research that proposes the use of kinetic Rigid Origami foldable surfaces to be used as roofs for spaces with big spans and the practical contribution that the Design Studio Surfaces INPLAY has brought to it
KOS - kinetic origami surface
In an increasingly technological, informed and demanding society Architecture should be able to answer to its space require-ments using materials and technological resources that today has at its service. Kinetic systems have been used by architects as an approach that embeds computation intelligence to create flexible and adaptable architectural spaces according to users’ changing needs and desires. This paper describes one possible way of exploring kinetic systems to develop a foldable surface with geometric patterns based on the rules of rigid origami. This surface aims to take advantage of the elastic ca-pacities given to a planar material by its folding. After folding the sur-face can assume different forms in order to create a range of spatial configurations ordered by a user through a remote control.info:eu-repo/semantics/publishedVersio
Origami tesselations: folding algorithms from local to global
Rigid Origami folding surfaces have very interesting qualities for Architecture and Engi-neering for their geometric, structural and elastic qualities. The ability to turn a flat element, isotropic, without any structural capacity, into a self-supporting element through folds in the material opens the door to a multitude of uses. Besides that the intrinsic geometry of the crease pattern may allow the surface to assume doubly curved forms while the flat element, before the folding, could never do it without the deformation of the material. (Schenk, 2011) (Demaine, 2011). The main objective of this PhD research is to reach a workflow from the definition of the geometry of the flat foldable surfaces to their implementation on a construction site. This paper will address mainly the steps taken to the parameterization of the Rigid Origami ge-ometries. We intend to establish a method to simulate the folding of regular crease pat-terns (tessellations) by understanding the geometric operations on the smallest set of faces (local) that can be reproduced to simulate the whole group (global).info:eu-repo/semantics/publishedVersio
Enterprise Collaboration Network for Transport and Logistics Services
Part 10: Collaboration Platforms; International audience; The development of the Single Window concept (unique access/contact point for composite services) for the multimodal door-to-door freight transport management is a complex endeavour that is being addressed by the European MIELE project. Led by port authorities, the project identified the need for a novel strategy to foster collaboration among stakeholders with a diversity of processes and technology. The multimodal perspective requires a convergence and thus collaboration of maritime, railway, road, and air transport facilities as it is the case for the need of traffic information for a real-time (re)planning if some accident is hindering the current route. This requires that traffic information from different operators is integrated into the freight transport routing planner. Furthermore, a unified coordination and operations management of the existing business processes is lacking. To integrate such contexts, an open enterprise collaboration network (ECoNet) infrastructure is presented and discussed.
Document type: Part of book or chapter of boo
Distributed process execution in collaborative networks
Processes are a central entity in enterprise collaboration. Collaborative processes need to be executed and coordinated in a distributed Computational platform where computers are connected through heterogeneous networks and systems. Life cycle management of such collaborative processes requires a framework able to handle their diversity based on different computational and communication requirements. This paper proposes a rational for such framework, points out key requirements and proposes it strategy for a supporting technological infrastructure. Beyond the portability of collaborative process definitions among different technological bindings, a framework to handle different life cycle phases of those definitions is presented and discussed. (c) 2007 Elsevier Ltd. All rights reserved
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