604,921 research outputs found
Bottom-up construction of ontologies
Presents a particular way of building ontologies that proceeds in a bottom-up fashion. Concepts are defined in a way that mirrors the way their instances are composed out of smaller objects. The smaller objects themselves may also be modeled as being composed. Bottom-up ontologies are flexible through the use of implicit and, hence, parsimonious part-whole and subconcept-superconcept relations. The bottom-up method complements current practice, where, as a rule, ontologies are built top-down. The design method is illustrated by an example involving ontologies of pure substances at several levels of detail. It is not claimed that bottom-up construction is a generally valid recipe; indeed, such recipes are deemed uninformative or impossible. Rather, the approach is intended to enrich the ontology developer's toolki
Horizontal Symmetry from the Bottom Up
A general method to derive horizontal symmetry from a mixing matrix is
reviewed. The technique has been applied to deduce leptonic symmetry from the
tri-bimaximal neutrino mixing matrix and three of its variations. The question
of how the quark mixing can be accommodated within the leptonic symmetry group
is discussed, including in this connection an example based on the group .Comment: Luxor09 talk, 7 page
institutional innovation from the bottom up?
A sustainable economy fulfills societal needs in a fundamentally different
way to the current economic system. Improvements to the efficiency of
existing technologies or practices appear insufficient for achieving
sustainable development within the planetary boundaries. Disruptive,
systemic and transformational changes appear necessary in order to replace
existing technologies and practices to establish a sustainable economy.
Such innovations often start out in niches; however, the scaling up and
the ultimate replacement of current socio-technical systems requires
governance to allow for the coordination of actors, the reorganization of
socio-technical systems and the mobilization and allocation of resources.
As governmental institutions are part of the current (non-sustainable)
systems and thereby fail to provide coherent, integrated and transformative
governance, we explore whether institutional innovation from non-state
actors can step in to provide governance of transformation processes.
Based on explorative qualitative case studies of networks in the food sector,
city planning and reporting tools, we analyze the potential of bottom-up
institutional innovations to coordinate actors in transformation processes
Generalised bottom-up holography and walking technicolour
In extradimensional holographic approaches the flavour symmetry is gauged in
the bulk, that is, treated as a local symmetry. Imposing such a local symmetry
admits fewer terms coupling the (axial) vectors and (pseudo)scalars than if a
global symmetry is imposed. The latter is the case in standard low-energy
effective Lagrangians. Here we incorporate these additional, a priori only
globally invariant terms into a holographic treatment by means of a
Stueckelberg completion and alternatively by means of a Legendre
transformation. This work was motivated by our investigations concerning
dynamical electroweak symmetry breaking by walking technicolour and we apply
our findings to these theories.Comment: 12 pages, 5 figure
- …
