3,842 research outputs found
Purification, growth, and characterization of Zn(x)Cd(1-x)Se crystals
The purification of starting materials which were used in the growth of Zn(x)Cd(1-x)Se (x = 0.2) single crystals using the traveling solution method (TSM) is reported. Up to 13 cm long single crystals and as grown resistivities of 6 x 10(exp 12) ohm/cm could be achieved. Infrared and Raman spectra of Zn(0.2)Cd(0.8)Se are also presented and discussed
A Semantic-based Workflow Choreography for Integrated Sensing and Processing
The University of Edinburgh and research sponsors are authorised to reproduce and distribute reprints and on-line copies for their purposes notwithstanding any copyright annotation hereon. The views and conclusions contained herein are the authorâ s and shouldnâ t be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of other parties.Real-time automatic and continuous information gathering through EcoGrid offers an unique and immense opportunity for long term ecological monitoring and planning.
However, the vast amount of raw data gathered must be dealt with efficiently and effectively so that they may be timely
turned into useable information to assist ecological management.
In addition, Ecological data tends to subject to environmental changes and exception-prone so that their qualities vary. Adaptive
business process modelling (BPM) techniques provide rich conceptualisation to support workflow systems to perform integrated
analytical and documentation tasks flexibly and efficiently. We present one such BPM and show how adaptive workflow systems,
like those developed at AIAI, can take advantage of Enterprise Models represented in FBPML to provide effective support to
users in real Grid environments
Enterprise Modelling: A Declarative Approach for FBPML
The University of Edinburgh and research sponsors are authorised to reproduce and distribute reprints and on-line copies for their purposes notwithstanding any copyright annotation hereon. The views and conclusions contained herein are the authorâs and shouldnât be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of other parties.Enterprise Modelling (EM) methods are well-recognised for their value in describing complex, informal domains in an organised
structure. EM methods are used in practice, particularly during the early stages of software system development, e.g. during the
phase of business requirements elicitation. The built model, however, has not always provided direct input to software system development. Despite the provision of adequate training to understand and use EM
methods, informality is often seen in enterprise models and presents a major obstacle. This paper focuses on one type of EM methods: business process modelling (BPM) methods. We advocate the use of a BPM language within a three-layer framework. The BPM language merges two main and complimentary business process representations, IDEF3 and PSL, to introduce a Fundamental Business Process Modelling Language (FBPML) that is designed for simplicity of use and under-pinned by rich formality that may be used directly to support software and workflow system development
Semantic Support for Visualisation in Collaborative AI Planning
The University of Edinburgh and research sponsors are authorised to reproduce and distribute reprints and on-line copies for their purposes notwithstanding any copyright annotation hereon. The views and conclusions contained herein are the authorâs and shouldnât be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of other parties.In the last decades, many advances have been made in intelligent planning systems. Significant improvements related to core problems, providing faster search algorithms and shortest plans have been proposed. However, there is a lack in researches
allowing a better support for a proper use
and interaction with planners, where, for instance, visualization can play an important role.This work proposes a general framework for visualisation of planning information using an approach based on semantic modelling. It intends to enhance the notion of knowledge-based planning applying it to other aspects of planning, such as visualisation. The approach consists in an integrated
ontology set and reasoning mechanism for
multi-modality visualisation destined to collaborative planning environments. This framework will permit organizing and modelling the domain from the visualisation perspective, and give a tailored support for presentation of information
Improving Semantics In Mobile Devices Profiling: A Model Conceptual Formalisation and Ontology Specification
The University of Edinburgh and research sponsors are authorised to reproduce and distribute reprints and on-line copies for their purposes notwithstanding any copyright annotation hereon. The views and conclusions contained herein are the authorâs and shouldnât be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of other parties.In this work we discuss and propose a new approach for semantic enhancement in mobile devices profiling. This work is motivated by the lack of semantic in existing profiling methods and is part of a broaden framework for visualisation of intelligent planning information in collaborative environments.
In this paper, before the discussion of this new model, its knowledge representation
and ontology specification concepts, we argue about problems in existing profiling methods
Detecting, Tracking and Counting Fish in Low Quality Unconstrained Underwater Videos
Abstract: In this work a machine vision system capable of analysing underwater videos for detecting, tracking and counting fish is presented. The real-time videos, collected near the Ken-Ding sub-tropical coral reef waters are managed by EcoGrid, Taiwan and are barely analysed by marine biologists. The video processing system consists of three subsystems: the video texture analysis, fish detection and tracking modules. Fish detection is based on two algorithms computed independently, whose results are combined in order to obtain a more accurate outcome. The tracking was carried out by the application of the CamShift algorithm that enables the tracking of objects whose numbers may vary over time. Unlike existing fish-counting methods, our approach provides a reliable method in which the fish number is computed in unconstrained environments and under several scenarios (murky water, algae on camera lens, moving plants, low contrast, etc.). The proposed approach was tested with 20 underwater videos, achieving an overall accuracy as high as 85%.
Workflow Collaboration with Constraint Solving Capabilities
The University of Edinburgh and research sponsors are authorised to reproduce and distribute reprints and on-line copies for their purposes notwithstanding any copyright annotation hereon. The views and conclusions contained herein are the authorâs and shouldnât be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of other parties.This paper describes our efforts to provide a collaborative problem solving architecture driven by semantic-based workflow orchestration and constraint problem solving. These technologies are based on shared ontologies that allows two systems of very different natures to communicate, perform specialised tasks and achieve common goals. We give an account of our approach for the workflow assisted collaboration with constraint solving capabilities. We found that systems built with semantic (web) based technologies is useful for collaboration and flexible to enhance the system with specialised capabilities. However, much care must be exercised before correct semantics may be exchanged and collaborations occur smoothly
An instability criterion for nonlinear standing waves on nonzero backgrounds
A nonlinear Schr\"odinger equation with repulsive (defocusing) nonlinearity
is considered. As an example, a system with a spatially varying coefficient of
the nonlinear term is studied. The nonlinearity is chosen to be repelling
except on a finite interval. Localized standing wave solutions on a non-zero
background, e.g., dark solitons trapped by the inhomogeneity, are identified
and studied. A novel instability criterion for such states is established
through a topological argument. This allows instability to be determined
quickly in many cases by considering simple geometric properties of the
standing waves as viewed in the composite phase plane. Numerical calculations
accompany the analytical results.Comment: 20 pages, 11 figure
Temporal Structures in Positron Spectra and Charge-Sign Effects in Galactic Cosmic Rays
We present the precision measurements of 11 years of daily cosmic positron fluxes in the rigidity range from 1.00 to 41.9 GV based on 3.4 Ă106 positrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The positron fluxes show distinctly different time variations from the electron fluxes at short and long timescales. A hysteresis between the electron fluxes and the positron fluxes is observed with a significance greater than 5 Ď at rigidities below 8.5 GV. On the contrary, the positron fluxes and the proton fluxes show similar time variation. Remarkably, we found that positron fluxes are modulated more than proton fluxes with a significance greater than 5 Ď for rigidities below 7 GV. These continuous daily positron fluxes, together with AMS daily electron, proton, and helium fluxes over an 11-year solar cycle, provide unique input to the understanding of both the charge-sign and mass dependencies of cosmic rays in the heliosphere
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