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A Self-Adaptive Service Provisioning Framework for 3G+/4G Mobile Applications
Get PDFIn light of the increasing acceptance of the
notion of Next Generation Networks (NGN),
which will result from the convergence of the
fixed and mobile telecommunications, Internet,
and entertainment sectors, there is a need for the
realization of next-generation service delivery
platforms to allow seamless and adaptive provisioning
of multimedia information and communication
services to mobile users. This means that
in such an NGN environment different end systems,
access networks, and service platforms have
to be integrated. For this highly heterogeneous
communications and services environment, we
propose a self-adaptive service provisioning middleware
framework (ASPF), which, by interoperating
with existing wireless and wireline service
delivery platforms, aims to enable seamless
omnipresent service provisioning to mobile users
anywhere, anytime, and in any context. The
ASPF is intended to “liberate” applications from
space and time limitations, networks, platforms,
and device dependences, minimize time-to-market
constraints, and eliminate major hurdles that
hinder the rapid deployment of new mobile services
and applications. Key to this goal is interworking/
integration with current SDPs, such as
IN/CAMEL, OSA/Parlay, and the emerging IMS
Redundancy vs. Imperfect Positioning for Context-dependent Services
No full textPositioning, as a key component of context, has been a driving factor in the development of ubiquitous computing applications throughout the past two decades. However, the precision is limited to specific applications, the availability limited to the provider of specific services. Combining multiple methods allows to recalibrate each other by means of data fusion. A novel architecture processes the data from pervasive devices penetrating everyday objects to the cheapest level. Location information can be inferred from infrastructure deployed for different purposes, only partly designed for positioning in the first place. The redundant heterogeneity of completely different recognition principles allows to tailor the perceived positioning probability to the specific requirements of the target application
Tacit Knowledge And Human Centred Systems: The Key To Managing The Social Impact Of Technology
Get PDFIn recent years the concept of knowledge management has become an important feature in automation literature, in particular as it relates to ICT (information and communications technology). To date, this literature focuses primarily upon knowledge, which can be extracted, explicitly stated and codified into large-scale databases or other knowledge capture devices and mechanisms. However, it is readily apparent that this notion of knowledge is extremely limited. In particular, in order to understand, appreciate and effectively design and manage complex technologies, we need to focus more on less-concrete forms of knowledge. These types of knowledge are often termed ‘tacit’ knowledge in order to emphasise their hidden nature. This paper reviews the current literature on tacit knowledge and relates it to current research and practise in AMAT and ICT. It then presents some empirical evidence to highlight the importance of tacit knowledge in engineering design and development work, and suggests a tacit knowledge-based framework
An Analysis of IPsec Deployment Performance in High and Low Power Devices
Get PDFVirtual Private Networks (VPNs) use the Internet or other network service as a backbone to provide a secure connection across a potentially hostile WAN. Such security guarantees provide the motivation for VPN deployment. This security does, however, come at a performance cost brought about by the increased processing overhead. This paper presents an investigation into these overheads. In particular, this investigation will consider different user resource availability based on the client platform in addition to router type and encryp- tion algorithms
Self-assembled arrays of ZnO nanoparticles and their application as varistor materials
Get PDFLinear arrays of ZnO nanoparticles have been successfully prepared by a simple sol–gel condensation reaction
involving chemical modifiers, followed by drying (80 uC) and calcination (500 uC). The calcined material (nanoarray
ZnO) is composed of approximately spherical nanoparticles of average diameter 21 ¡ 3 nm, selfassembled
to form arrays extending in length to 2–4 mm. The morphology of the ZnO is found to depend
sensitively on the amounts of chemical modifiers present. In their absence the ZnO produced (nano-ZnO) is an
unstructured agglomerate of nanoparticles. The mechanism for formation of these linear arrays has been
investigated by examining the intermediates formed at 80 uC and 250 uC using XRD and TEM and by
following the decomposition reactions using TGA and DSC. Varistors prepared from the nano-array ZnO by
sintering (1050 uC) with appropriate mixtures of metal oxides showed a breakdown voltage of 786 ¡ 30 V
mm21, which is substantially higher than that of samples prepared under similar conditions from either micronsized
commercial ZnO (507 ¡ 30 V mm21) or from nano-ZnO (683 ¡ 30 V mm21)
Resources Discovery and Management using Policies in Smart Spaces
Get PDFThis paper presents a new hierarchical Policy Based Management (PBM) architecture that facilitates the description and automatic discovery of services and devices in Smart Space environments and the specification of high-level policies that control access to these resources in coexisting Managed Zones (M-Zones).
The approach is performed in two phases. The first one consists of defining a generic information model of all resources that can be managed in such a space and a specification of a set of high-level policies to express the access control policy of each M-Zone. Both models are specified using the DMTF CIM. (For the next iteration, it is planned to use the DEN-ng model, extended with new specific objects). The second phase is more dynamic and uses a novel discovery protocol based on COPS to identify the various components that are present in a particular environment. This protocol is named COPS-SD (COPS extensions for Service Discovery usage)
Acquisition, Modelling and Visualisation of Inter-domain Routing Data
No full textThe INTERMON project aims at inter-domain IP QoS monitoring, measurement and modelling. An important part of this project is exploring the use of inter-domain data in these tasks. Inter-domain topology information provides a level of abstraction, which is much higher than at intra-domain level. The impact of inter-domain routing events on end-to-end QoS measurements is expected to be more drastic than the effect of possible intra-domain routing events in each of the domains. One of the scientific results expected from the INTERMON project is the validation or rejection of this hypothesis. This paper demonstrates how the INTERMON project captures, models and visualises this inter-domain topology information. The INTERMON project is funded by the European Commission under the FP5 Programme: IST-2001-34123. The approach proposed in this paper is less resource intensive since the independent BGP-4 probe does not access backbone routers
REVISING THE THEORY OF SOCIALLY INCLUSIVE SYSTEMS ENGINEERING SOCIAL IMPACT CONSIDERATIONS IN DISTRIBUTED ASSISTIVE SYSTEMS FOR THE LEARNING DISABLED
Get PDFthe relationship between humans and advanced technology can be viewed as a network of interests of technical and non-technical agents. Drawing upon instrumental realist approaches as set out in agent network theory the paper describes a project currently underway in Ireland and Bulgaria which delivers comprehensive, assistive systems for people with learning disabilities. These systems address many of the difficulties associated with current assistive technology (AT) programmes, problems typically associated with the narrow focus of AT upon technology solutions. Whilst limited, it delivers a sound ethical basis for technology-centred programmes, and new trajectories for engineering research
Mode formation in broad area quantum dot lasers at 1060 nm
Get PDFAn analysis of the transverse and longitudinal mode structure of broad area quantum dot lasers emitting at 1060 nm
is presented. In particular, temperature is shown to play an important role in the stabilisation of the transverse mode
structure of the devices. In addition, the investigation of the interaction between these transverse modes, through the
measurement of the spatial intensity correlation, shows that the laser retains some modal properties in the unstable
regime. Finally, measurements of spectral correlations between longitudinal mode groups display a strong dependency
on their respective transverse mode structures indicating the importance of spatial overlap
Measurement of linewidth enhancement factor in self-assembled quantum dot semiconductor lasers emitting at 1310 nm
Get PDFMeasurements of the linewidth enhancement factor (also termed the aparameter)
for quantum dot semiconductor lasers emitting at 1310 nm
in both single and multiple transverse modes are presented. Values
between 1.5 and 3.0 were measured depending on the device length.
In addition, its spectral dependence within the inhomogeneously
broadened ground and excited state is investigated