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User-Centric Adaptive Access Control and Resource Configuration for Ubiquitous Computing Environments
Get PDFProvision of adaptive access control is key to allowing users harness the full potential of ubiquitous computing environments. In this paper, we introduce the M-Zones Access Control (MAC) process, which provides user-centric attribute-based access control, together with automatic reconfiguration of resources in response to the changes in the set of users physically present in the environment. User control is realised via user-specified policies, which are analysed in tandem with system policies and policies of other users, whenever events occur that require policy decisions and associated configuration operations. In such a system users' policies may habitually conflict with system policies, or indeed other users' policies; thus, policy conflict detection and resolution is a critical issue. To address this we describe a conflict detection/resolution method based on a policy precedence scheme. To illustrate the operation of the MAC process and its conflict detection/resolution method, we discuss its realisation in a test bed emulating an office-based ubiquitous computing environment
THE DYNAMIC ADAPTATION OF POLICIES IN UBIQUITOUS ENVIRONMENTS, WITH CONTEXTUAL INFORMATION AS THE CATALYST
No full textThis report proposes a policy refinement process design specifically to assist in the management of ubiquitous environments. The principal intent of these environments is to provide user-centric services, devices, interfaces and information. This objective together with other characteristics of ubiquitous environments, namely volatility, invisibility, heterogeneity and accessibility, introduces new and redirects existing management challenges. The flexibility of policy-based management makes it an attractive approach on which to develop an architecture that supports the management of ubiquitous computing environments. The proposed policy refinement architecture uses system requirements along with applicable context information to respond, in an adequate and timely manner, to changes in the underlying infrastructure, user requirements and system requirements
Initial approach toward self-configuration and self-optimization in IP networks
Get PDFThe growing heterogeneity and scalability of Internet services has complicated, beyond human capabilities, the management of network devices. Therefore, a new paradigm called autonomic networking is being introduced to control, in an efficient and automatic manner, this complex environment. This approach aims to enhance network elements with capabilities that allow them to choose their own behavior for achieving high-level directives. This so called autonomic network element should be able to optimize its configuration, ensure its protection, detect/repair unpredicted conflicts between services requirements and coordinate its behavior with other network elements. In this paper, we present a research activity that investigates this new concept, and applies it to facilitate the configuration and the optimization of a multi-services IP network. This approach is a first step toward building a self-configured and self-optimized IP network that automatically supports the QoS requirements of heterogeneous applications without any external intervention. Different paradigms have been explored in order to model this behavior and to render network equipment autonomic. A laboratory prototype has been developed to highlight the autonomic behavior of the network to achieve heterogeneous QoS requirements of multimedia and data applications
Measurement of macular pigment: Raman spectroscopy versus heterochromatic flicker photometry
Get PDFPURPOSE. There are several techniques for measuring macular pigment (MP) in vivo, of which Raman spectroscopy (RS) is a recently developed objective method. This study reports the reproducibility, test-retest variability, and validity of RS MP readings, by comparing them with heterochromatic flicker photometry (HFP). METHODS. MP was measured with HFP and RS in 120 healthy subjects, and the latter technique was also used on two separate occasions in a sample of 20 subjects to investigate the intersessional variability of readings. Intrasessional reproducibility of RS MP measurements was also calculated. In addition, serum concentrations of lutein (L) and zeaxanthin (Z) were measured and correlated with both RS and HFP NIP readings. RESULTS. Mean (+/-SD) NIP in the right eye was 0.279 +/- 0.145 and 0.319 +/- 0.155 with RS and HFP, respectively. The differences between corresponding MP readings taken on RS and HFP lay within the Bland-Altman 95% limits of agreement for the two instruments in 93.6% and 94.4% of cases in the right and left eyes, respectively. Intrasessional reproducibility of RS readings, expressed as the coefficient of variation, was 8.42% +/- 7.12%. Ninety-five percent of MP readings taken with RS on two separate occasions lay within the 95% limits of agreement for the two sessions. A positive, but insignificant, relationship was observed between RS and HFP MP readings and serum concentrations of L and Z (RS, P = 0.356; HFP, P = 0.540). CONCLUSIONS. RS, an objective method of measuring NIP levels in vivo, exhibits acceptable reproducibility and test-retest variability. The results demonstrated good correlation between RS and HFP measurements of MP, thus authenticating RS against a validated psychophysical technique of measuring MP. However, investigators should use only one of these instruments for the duration of any given study because of differences in the scientific rationale, and the factors that influence RS and HFP measurements of MP
Electron-hole asymmetry and two-state lasing in quantum dot lasers
No full textWe study the decrease of the ground-state output with increasing current in two-state quantum dot lasing. We show that the asymmetry in the thermal population redistribution breaks the symmetric dynamical evolution of the electron-hole pairs. This fully explains the transition from two-state to single-state lasing observed experimentally. The model also reproduces the temperature dependence of the two-state lasing
Infrastructures for Mobile Government Services
No full textThis paper describes a range of infrastructural issues that impact on the way that mobile government services are being and will be designed and deployed. In this sense, mobile government services are just like many other areas of mobile computing, dominated by the push to deploy Internet technologies on wireless networks. The first issue that is addressed is that of the ownership of the infrastructure. It is argued that the concept of Open Access Networks (OANs) is an important one, especially for publicly funded wireless networks. The next issue addressed is the use of IPv6 instead of IPv4 as the main transport technology. Political and technical reasons for the choice of IPv6 are discussed. Finally the paper addresses the software used to develop services and touches on the debates on appropriate middleware architectures for mobile services
CELTIC Initiative Project Madeira: A P2P Approach to Network Management
Get PDFThe vision of the Celtic-Initiative project Madeira is to provide novel technologies for a logically meshed Network Management System that facilitates self-management and dynamic behaviour of nodes within networks. These approaches should enable adaptable services and the management of network elements of increasing number, heterogeneity and transience, thereby reducing OPEX. In this paper, we set the scope for investigations within the project and give an outline of our approach. We present a scenario that challenges today’s state of the art in Network Management and upon which we are building our case study for a detailed investigation of feasibility. Finally, we describe a preliminary conceptual system architecture and application data model, and give an insight into the expected final project results
Einstein and the Atomic Theory
Get PDFIn the year 1905, a young Albert Einstein published a number of scientific papers that changed physics forever. The best known of these, the Special Theory of Relativity, quickly established the young Einstein as a scientist of note (see J.IEI vol. 59:6) and led to Einstein’s General Theory
of Relativity, one of the pillars of modern physics. In a second paper, Einstein published a controversial proposal concerning the nature of light that later formed a cornerstone of quantum theory, the revolutionary theory that underpins much of modern science and technology (see J.IEI
vol. 59:7). Incredibly, the young Einstein made a third ground-breaking advance in 1905.
He published an analysis that pointed the way towards a crucial test of the reality of atoms, and of the validity of the laws of thermodynamics. The outcome of that test now underpins much of modern science, from our view of the atomic nature of matter to our understanding of meteorology and other complex systems
Empirical Algebraic Modelling of Lactation Curves Using Irish Data
Get PDFThe purpose of this study was to find a well-fitting,robust, single equation model to describe the shape of lactation curves for Irish dairy cows. The suitability of a number of algebraic models that depict lactation curves was examined, using Irish test day data. The analysis was carried out on a total of 14,956 lactation records from commercial and experimental herds and included both autumn and spring calving animals ‘Goodness of fit’ and adherence of the various models to the assumptions of
regression analysis were examined. Multicollinearity posed a severe problem in the application of the best-fit model but omitting one of the variables from the estimation
procedure reduced this effect. The modified model, referred to as the Ali-B model, is a single equation model that can be easily updated and incorporated into computer code.
This is in contrast with the Standard Lactation Curve (SLAC) method, a method of interpolation, which is currently adopted by the Irish industry. The effects of seasonal factors on milk production were estimated and added to the Ali-B model to create a production profile for cows calving in specific months. The Ali-B model provides an
acceptable level of accuracy in representing the shape of the lactation curve for Irish dairy cows, and can be easily modified for different environmental scenarios
Event-Marketing: When Brands Become 'Real-Lived' Experiences
Get PDFWhether one agrees or disagrees with the philosophical idea of postmodernism and its value for marketing practice (Brown 1994), there is no denying that a number of the conditions proposed by Firat (1991) determine consumer behaviour and the way of doing business in today’s affluent societies (Cova and Cova 2002; Patterson 1998). Indeed, due to the majority of industries increasingly reaching a state of saturation in recent years, many products have matured to such an extent that they can no longer be distinguished on their quality and functional benefits alone (Weinberg 1993; Kroeber-Riel 1984). Subsequently, the role of brand management has already shifted from providing a “mere” means of identification towards creating brand identities and communicating brand visions through the addition of sign values and meanings (de Chernatony 2001; Weinberg 1992). However, the reliance of marketers on identical symbols and sign values has resulted in standardised, interchangeable brand communication designs (Weinberg and Gröppel 1989) and comparable claims that are pushed through the same channels, blurring any existing brand distinctions even further (Schmitt 1999; Kroeber-Riel 1984). Therefore, the emphasis of branding should be placed on stimulating hyperreal experiences for consumers to meet the changing needs in affluent (postmodern) societies.
As a pull strategy, event-marketing offers marketers an innovative approach in marketing communications that meets those conditions. By staging marketing-events, consumers are encouraged to experience the brand values and vision as a 3-dimensional hyperreality (Wohlfeil and Whelan 2005a). In other words, similar to a theme park the brand identity is turned into a “real-lived” multi-sensual experience. Because personally “lived” experiences tend to be stronger in determining consumers’ notion of reality than the “second-hand” experiences traditionally communicated by advertising (Weinberg and Nickel 1998), event-marketing is better equipped to anchor multi-sensual brand experiences in the world of consumer feelings and experiences (Weinberg and Gröppel 1989). By meeting consumers’ growing need for experiential consumption in affluent societies, they make a genuine contribution to their perceived quality of life (Wohlfeil and Whelan 2005b, 2004). But is it just another postmodern craze or an exciting new way for marketers to communicate brand values to consumers in affluent societies?
Therefore, the objective of this paper is to introduce the concept of event-marketing to a broader audience and to discuss its role within marketing communications as well as its impact on the changing communications landscape. By presenting empirical evidence from a qualitative field experiment at the Guinness Storehouse in Dublin, the paper will outline how brands can be communicated as experiential 3-dimensional real-lived experiences, which would strengthen the emotional attachment to the brand by developing and implementing creative event-marketing strategies. Consequently, the findings will narrow the information gap by increasing the perceived fit between consumers’ experiential needs and a brand’s contribution to their quality of life