Model-driven systems development and integration environment

Telecommunications operators are undergoing massive transformations in order to metamorphose themselves into the ICT world and compete with agile, lean IT organisations. The main challenges facing telecommunications operators, such as BT, are to reduce costs and increase agility in deploying software systems for provisioning ICT services. Despite using reusable capabilities and COTS packages, the major source of increased cost lies in the heavy integration tax we incur for integrating diverse systems implemented on diverse platforms and middleware, with heterogeneous data and process models. This paper looks at cost implications of lengthy and often manual migration to-and-from systems and platforms, and shows the clear business benefits of model-driven development (MDD) as defined by the Object Management Group (OMG). It is clearly demonstrated that model-driven development has matured into a practical, industrialised, scalable and evolvable technology, culminating from decades of R&D on specification and design languages, executable formalisms and domainspecific languages and language transformations.     

Entities,identities, identifiers and credentials — what does it all mean?

This paper looks at the concepts of entities, identities, identifiers and credentials, their definitions, and how they combine to authenticate an identity to an account, or function, within a service. Credentials can be divided into several different types on the basis of their use, origin and characteristics. In particular, types such as composite, dynamic and derived credentials will be considered, and their applicability within an identity management system. Each credential must be managed through its entire life cycle from initial registration, general use and suspension, to deletion. The notion of public (i.e. freely distributable) and private (i.e. known only to you) aspects of a credential is explored. The bindings, by trusted third parties, of identifiers and public credentials into permits and instruments of proof is explained along with the convenience, but greater exposure, of local information. Several scenarios are analysed in terms of how different types of credentials are employed during the authentication process.     

Security issues in hybrid networks with a satellite component

Satellites are expected to play an increasingly important role in providing broadband Internet services over long distances in an efficient manner. Most future networks will be hybrid in nature - having terrestrial nodes interconnected by satellite links. Security is an important concern in such networks, since the satellite segment is susceptible to a host of attacks, including eavesdropping, session hijacking and data corruption. In this article we address the issue of securing communication in satellite networks. We discuss various security attacks that are possible in hybrid satellite networks, and survey the different solutions proposed to secure data communications in these networks. We look at the performance problems arising in hybrid networks due to security additions like Internet security protocol (IPSec) or secure socket layer (SSL), and suggest solutions to performance-related problems. We also point out important drawbacks in the proposed solutions, and suggest a hierarchical key-management approach for adding data security to group communication in hybrid networks.     

Linear demosaicing inspired by the human visual system.

There is an analogy between single-chip color cameras and the human visual system in that these two systems acquire only one limited wavelength sensitivity band per spatial location. We have exploited this analogy, defining a model that characterizes a one-color per spatial position image as a coding into luminance and chrominance of the corresponding three colors per spatial position image. Luminance is defined with full spatial resolution while chrominance contains subsampled opponent colors. Moreover, luminance and chrominance follow a particular arrangement in the Fourier domain, allowing for demosaicing by spatial frequency filtering. This model shows that visual artifacts after demosaicing are due to aliasing between luminance and chrominance and could be solved using a preprocessing filter. This approach also gives new insights for the representation of single-color per spatial location images and enables formal and controllable procedures to design demosaicing algorithms that perform well compared to concurrent approaches, as demonstrated by experiments.     

The effect of laser radiation on the formation of oriented cadmium sulfide layers under highly nonequilibrium conditions

The effect of low-power laser radiation on the formation of oriented cadmium sulfide layers from a vapor phase on a substrate cooled with liquid nitrogen (highly nonequilibrium conditions) is studied. The results of technological experiments, the results of a study of electron diffraction (electron diffraction patterns), and condensation diagram data are reported. It is found that, depending on the substrate temperature, laser radiation can both improve and worsen the crystal quality of films. It is shown that a condensation diagram of cadmium sulfide layers formed on a substrate exposed to low-power laser radiation is shifted to higher temperatures relative to a condensation diagram obtained without laser radiation. The experimental results are interpreted in the context of a solitonic heteroepitaxy model.     

High performance biofilm process for treating wastewater discharged from coal refining plants containing nitrogen, cyanide and thiocyanate.

Wastewater discharge from coal refining plants contains a number of biologically toxic compounds; 2000-2500 mg/l of COD of which 40% is composed of phenol, 100-400 mg/l of thiocyanate, 10-40 mg/l of cyanide, 100-250 mg/l of NH4+-N and 150-300 mg/l of total nitrogen. In order to treat this kind of high strength wastewater, we have developed a high performance biofilm process using fluidizing bio-carriers of the tube chip type. The fluidizing biofilm carriers are made of a composite of polyethylene and several inorganic materials, whose density is controlled at 0.97-0.98 g/ml. The fluidizing biofilm carriers show sound fluidization characteristics inside bioreactors. The wastewater is treated using three consecutive series reactors in oxic-anoxic-oxic arrangement. Each reactor is charged with the fluidizing biofilm carriers of 50 vol%. Furthermore, newly cultured active microorganisms for the thiocyanate biodegradation are added in the biofilm process. At total hydraulic retention time of 2.2 days, this process can achieve steady state removal efficiencies: COD, 99%; thiocyanate, 99%; NH4+-N, 99% and total nitrogen, 90%.     

iShopFloor: an Internet-enabled agent-based intelligent shop floor

Global competition is driving manufacturing companies to change the way they do business. New kinds of shop floor control systems need to be implemented for these companies to respond quickly to changing shop floor environments and customer demands. This paper presents a new concept called iShopFloor-an intelligent shop floor based on the Internet, web, and agent technologies. It focuses on the implementation of distributed intelligence in the manufacturing shop floor. The proposed approach provides the framework for components of a complex control system to work together as a whole rather than as a disjoint set. It encompasses both information architecture and integration methodologies. The paper introduces the basic concept of iShopFloor, a generic system architecture, and system components. It also describes the implementation of eXtensible Markup Language message services in iShopFloor and the application of intelligent agents to distributed manufacturing scheduling. A prototype environment is presented, and some implementation issues are discussed.     

Wideband and compact folded loop antenna

A simple and successful design method that yields a wideband and compact antenna without a ground plane is proposed. The antenna, referred to as the folded loop antenna, can, with the right parameters, achieve wideband characteristics. Calculated and measured results agree well and more than 50% bandwidth (return loss /spl les/-10 dB) is obtained.     

An integrated system to remote monitor and control anaerobic wastewater treatment plants through the internet.

The TELEMAC project brings new methodologies from the Information and Science Technologies field to the world of water treatment. TELEMAC offers an advanced remote management system which adapts to most of the anaerobic wastewater treatment plants that do not benefit from a local expert in wastewater treatment. The TELEMAC system takes advantage of new sensors to better monitor the process dynamics and to run automatic controllers that stabilise the treatment plant, meet the depollution requirements and provide a biogas quality suitable for cogeneration. If the automatic system detects a failure which cannot be solved automatically or locally by a technician, then an expert from the TELEMAC Control Centre is contacted via the internet and manages the problem.     

Remotely powered addressable UHF RFID integrated system

This paper presents a fully integrated remotely powered and addressable radio frequency identification (RFID) transponder working at 2.45 GHz. The achieved operating range at 4 W effective isotropically radiated power (EIRP) base-station transmit power is 12 m. The integrated circuit (IC) is implemented in a 0.5 /spl mu/m silicon-on-sapphire technology. A state-of-the-art rectifier design achieving 37% of global efficiency is embedded to supply energy to the transponder. The necessary input power to operate the transponder is about 2.7 /spl mu/W. Reader to transponder communication is obtained using on-off keying (OOK) modulation while transponder to reader communication is ensured using the amplitude shift keying (ASK) backscattering modulation technique. Inductive matching between the antenna and the transponder IC is used to further optimize the operating range.