242 research outputs found
Use of higher-protein diets for body composition improvement in non-obese, active individuals
Excavations at cathole cave, Gower, Swansea
The discovery of an engraving in Cathole Cave in 2010 led to a decision to grille the cave. In 2012 excavations took place in the cave ahead of the grilling. Two areas of the cave were excavated; Trench A demonstrating that the cave held a faunal occupation dating to MIS 3, at a time, or times, between 50,000 and 30,000 BP. Two flint blades of Upper Palaeolithic appearance were discovered along with a faunal assemblage from within the shallow deposits across the line of the grille. The work demonstrated that the earlier excavations in the cave by Col. E.R. Wood were extensive and at this point in the cave he excavated to bedrock. The standing section (Trench B) which he left exposed further along the main cave passage was also cleaned, recorded and sampled. The deposits contain a faunal assemblage dominated by microfauna, but no cultural artefacts were found. The dating of key animal bones, the analysis of the microfauna and the sedimentological analysis have together enabled a picture to be developed of the changes in this section from the mid-Devensian to Late Glacial and Holocene
Manufacturability verification through feature-based ontological product models
To achieve efficient, fast and cost effective production, designers must consider all the manufacturing stages a product has to go through. A case study in a manufacturing setup shows that owing to the differences in perception of an engineering component, the coordination between design and manufacturing becomes difficult. Semantic interoperability problems are therefore faced when knowledge sharing for the purpose of manufacturability verification is attempted through computer-based knowledge bases. Ontologies have a reputation for solving semantic interoperability problems. Combined with shape feature-based models of components, ontologies provide a basis for seamless knowledge sharing. This article demonstrates the use of ontologies for analyzing the manufacturability of engineering components in the early design stages. This is done by developing shape feature-based ontological models of these components and associating manufacturability knowledge with these models. To achieve this, an ontological modelling technique is proposed that uses shape feature-based geometrical models of engineering components as building blocks. The knowledge associated with these models to demonstrate their use for manufacturability verification is derived from the findings of a case study also detailed in this article. © IMechE 2012
Mediation of foundation ontology based knowledge sources
Ontologies are helpful in giving interoperable structures to sources of knowledge and information. This interoperability, however, is greatly hindered by the heterogeneity of independently developed ontologies which in turn increases the requirements for mediation systems to reconcile the differences. A core concepts ontology for a certain domain contained by a foundation ontology can be used to alleviate this problem and to facilitate the reconciliation efforts. Possible differences in the use of concepts from the core concepts to model entities in domain ontologies can be prevented by binding the domain ontology developers to some rules. These rules can be particularly useful for domain ontologies requiring some kind of traceability of their concepts in the foundation ontology. The mediation system can then use this traceability to establish similarities between two ontologies. Software applications, like the one explained in this paper, can then be developed to perform the mediation task automatically and accurately
Gap analysis of ontology mapping tools and techniques
Mapping between ontologies provides a way to overcome any dissimilarities in the terminologies used in two ontologies. Some tools and techniques to map ontologies are available with some semi-automatic mapping capabilities. These tools are employed to join the similar concepts in two ontologies and overcome the possible mismatches.Several types of mismatches have been identified by researchers and certain overlaps can easily be seen in their description. Analysis of the mapping tools and techniques through a mismatches framework reveals that most of the tools and techniques just target the explication side of the concepts in ontologies and a very few of them opt for the conceptualization mismatches. Research therefore needs to be done in the area of detecting and overcoming conceptualization mismatches that may occur during the process of mapping. The automation and reliability of these tools are important because they directly affect the interoperatbility between different knowledge sources
Enabling interoperable manufacturing knowledge sharing in PLM
Traditional approaches to integrated information sharing fall far short of meeting the requirements for the seamless sharing of knowledge to support enterprise activities through the product lifecycle. Recent advances in ontological approaches to manufacturing knowledge organisation is showing promise that a step change in knowledge sharing capability can be achieved from the application of rigorous logic based languages, combined with methods for modelling context relationships. This paper discusses the issues involved in providing an interoperable manufacturing knowledge sharing environment and proposes a manufacturing foundation ontology as a key requirement for interoperable manufacturing knowledge sharing
Verification of knowledge shared across design and manufacture using a foundation ontology
Seamless computer-based knowledge sharing between departments of a manufacturing enterprise is useful in preventing unnecessary design revisions. A lack of interoperability between independently developed knowledge bases, however, is a major impediment in the development of
a seamless knowledge sharing system. Interoperability, being an ability to overcome semantic and syntactic differences during computer-based knowledge sharing can be enhanced through the use of foundation ontologies. Foundation or core ontologies can be used to overcome differences existing
in more specialized ontologies and to ensure a seamless sharing of knowledge. This is because these ontologies provide a common grounding for domain ontologies to be used by different functions or departments. This common bases can be used by mediation and knowledge verification systems to
authenticate the meaning of knowledge understood across different domains. For this reason, this research proposes a knowledge verification framework for developing a system capable of verifying
knowledge between those domain ontologies which are developed out of a common core or
foundation ontology. This framework makes use of ontology logic to standardize the way concepts from a foundation and core-concepts ontology are used in domain ontologies and then by using the same principles the knowledge being shared is verified
A Pilot Study of Circulating Endothelial and Hematopoietic Progenitor Cells in Children With Sarcomas
Utilizing a multiparametric flow cytometry protocol, we assessed various cell types implicated in tumor angiogenesis that were found circulating in the peripheral blood of children with sarcomas (cases) based on their cell surface antigen expression. Circulating endothelial cells (CECs), endothelial colony-forming cells (ECFCs), and the ratio of 2 distinct populations of circulating hematopoietic stem and progenitor cells (CHSPCs), the proangiogenic CHSPCs (pCHSPCs) and nonangiogenic CHSPCs (nCHSPCs) were enumerated. Multiparametric flow cytometry was analyzed in cases at baseline and at 4 additional timepoints until the end of treatment and levels compared with each other and with healthy controls. At all timepoints, cases had significantly lower levels of CECs, but elevated ECFCs and a pCHSPC:nCHSPC ratio compared with controls (all P-values <0.05). There was no significant difference in any of the cell types analyzed based on tumor histology, stage (localized vs. metastatic), or tumor size. After treatment, only the CECs among the complete responders were significantly lower at end of therapy (P<0.01) compared with nonresponders, whereas the ECFCs among all cases significantly increased (P<0.05) compared with baseline. No decline in the pCHSPC:nCHSPC ratio was observed despite tumor response. On the basis of these results, a validation of CECs as prognostic biomarker is now warranted
Towards the ontology-based consolidation of production-centric standards
Production-centric
international
standards
are
intended
to
serve
as
an
important
route
towards
information
sharing
across
manufacturing
decision
support
systems.
As
a
consequence
of
textual-based
definitions
of
concepts
acknowledged
within
these
standards,
their
inability
to
fully
interoperate
becomes
an
issue
especially
since
a
multitude
of
standards
are
required
to
cover
the
needs
of
extensive
domains
such
as
manufacturing
industries.
To
help
reinforce
the
current
understanding
to
support
the
consolidation
of
production-centric
standards
for
improved
information
sharing,
this
article
explores
the
specification
of
well-defined
core
concepts
which
can
be
used
as
a
basis
for
capturing
tailored
semantic
definitions.
The
potentials
of
two
heavyweight
ontological
approaches,
notably
Common
Logic
(CL)
and
the
Web
Ontology
Language
(OWL)
as
candidates
for
the
task,
are
also
exposed.
An
important
finding
regarding
these
two
methods
is
that
while
an
OWL-based
approach
shows
capabilities
towards
applications
which
may
require
flexible
hierarchies
of
concepts,
a
CL-based
method
represents
a
favoured
contender
for
scoped
and
facts-driven
manufacturing
applications
Extending product lifecycle management for manufacturing knowledge sharing
Product lifecycle management provides a framework for information sharing that promotes various types of decisionmaking
procedures. For product lifecycle management to advance towards knowledge-driven decision support, then this
demands more than simply exchanging information. There is, therefore, a need to formally capture best practice
through-life engineering knowledge that can be fed back across the product lifecycle. This article investigates the interoperable
manufacturing knowledge systems concept. Interoperable manufacturing knowledge systems use an expressive
ontological approach that drives the improved configuration of product lifecycle management systems for manufacturing
knowledge sharing. An ontology of relevant core product lifecycle concepts is identified from which viewpoint-specific
domains, such as design and manufacture, can be formalised. Essential ontology-based mechanisms are accommodated
to support the verification and sharing of manufacturing knowledge across domains. The work has been experimentally
assessed using an aerospace compressor disc design and manufacture example. While it has been demonstrated that the
approach supports the representation of disparate design and manufacture perspectives as well as manufacturing knowledge
feedback in a timely manner, areas for improvement have also been identified for future work
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