First experiences with Personal Networks as an enabling platform for service providers

By developing demonstrators and performing small-scale user trials, we found various opportunities and pitfalls for deploying personal networks (PNs) on a commercial basis. The demonstrators were created using as many as possible legacy devices and proven technologies. They deal with applications in the health sector, home services, tourism, and the transportation sector. This paper describes the various architectures and our experiences with the end users and the technology. We conclude that context awareness, service discovery, and content management are very important in PNs and that a personal network provider role is necessary to realize these functions under the assumptions we made. The PNPay Travel demonstrator suggests that PN service platforms provide an opportunity to develop true trans-sector services

Computational modeling of integrated-optical waveguides

Electrical Engineering, Mathematics and Computer Scienc

Using Advanced Integration Concepts for Trans-sector Innovation- View and Status

Electrical Engineering, Mathematics and Computer Scienc

First experiences with Personal Networks as an enabling platform for service providers

Electrical Engineering, Mathematics and Computer Scienc

Holonic architecture of the smart grid

With the growing concerns about sustainable energy, energy efficiency and energy security, the electrical power system is undergoing major changes. Distributed energy sources are becoming widely available at the lower parts of the grid. As a result, more and more end consumers are transforming from passive consumers to active “prosumers” that can autonomously generate, store, import and/or export power. As prosumers increasingly dominate the power system, the system demands capability that allows enormous number of stakeholders with heterogeneous types to exchange power on the grid. Unfortunately, the classical power system cannot efficiently handle this scenario since it was designed for centralized power distribution. Thus, restructuring the rather old power system is indispensable. In this paper, we apply the holonic approach to structure the smart grid as a system that is bottom-up organized from autonomous prosumers that are recursively clustered at various aggregation layers. Based on this, we present a control architecture of the smart grid using holonic concepts. Our control architecture is characterized by autonomy of the prosumers, distributed control, recursive self-similar control structures at different aggregation levels. Further, we present a service oriented architec-ture (SOA) framework that models the control functions that make up the holonic control architecture. Our proposed control architecture is tested using a simulation set-up.Intelligent SystemsElectrical Engineering, Mathematics and Computer Scienc

Designing reliable and resilient smart low-voltage grids

The electric power grid is a critical infrastructure that delivers electricity from power generation sources to consumers. At this time, renewable and distributed sources of electricity as well as new technologies that introduce large loads are significantly changing load profiles in low-voltage grids. This trend calls for reassessing the structure of low-voltage grids to examine if they can safely accommodate the new load profiles. The future smart grid will also rely on information and communications networks to support decentralized power distribution. The information and communications network nodes may depend on the grid for power supply, leading to bidirectional interdependence between the two types of networks that could affect the reliability of the power grid.This paper focuses on the problem of enhancing the reliability of future low-voltage grids by improving their structure and dealing with their interdependence with information and communications networks. The paper investigates the structural features of a low-voltage grid and assesses their influence on the ability of the grid to handle new load profiles. Concepts from complex networks theory are used to derive relevant structural metrics that characterize the structural properties of low-voltage grids and performance metrics are proposed to assess their operational performance. Several low-voltage networks are analyzed under various loading scenarios to observe the influence of structural metrics of a low-voltage grid on its operational metrics. Based on this analysis, a constraint programming formulation is proposed for the cost-optimal and robust structural design of a low-voltage grid. In addition, a design algorithm is proposed that considers the interdependence of information and communications network nodes on power grid nodes to increase the reliability of the grid.Network Architectures and Service

Renaissance of the Incumbents; Network Visions from a Human Perspective

Electrical Engineering, Mathematics and Computer Scienc

The value (driven) web

This paper presents a vision on the importance of values and ethical aspects in web science. We create(d) the Internet, but now the Internet (technology) is shaping our world increasingly: the way we experience, interact, transact, conduct business et cetera. The Internet is ubiquitous and vital to many aspects of our society; it is substituting some of our existing infrastructures and its traffic becomes a reflection of our society. The complexity of the Internet grows fast and might at some point transcend that of ourselves. At the same time the Internet escapes our normative, ethical control. Though it is value-laden, the process of embedding values in internet technology is mostly implicit and obscured by both the strong technological focus and distributive nature of internet technology and services. This distributive nature reflects amongst other things the result of an increased institutionalization of functionally decomposed economical and societal products and services in all the sectors that contribute to the GDP. This trend of decomposition clashes with the desires of all “prosumers” using the Internet and require integrated, composed products and services that they can identify and associate with in a human way. User values and expectations must be met by the products and services. This is a potential tipping point where supply and demand, producers and consumers, political society and technology may be drifting apart. Thus, web science is confronted with a crucial challenge and a huge responsibility. We argue that in order for the Internet to evolve and mature into a long term sustainable organic extension of our society, we must explicitly recognize the importance of values. This is a first step towards embedding the values that society recognizes as important. Values concerned do not solely deal with privacy, but also with security, transparency, trust, user autonomy et cetera. The challenge for all involved in the development of the Internet and in the provision of services is to define the values that matter and to bring them to bear upon technology, software architecture, standards, code et cetera. In this paper, we set out to identify some of the vital values and norms that will enable us to mould the Internet according to societal ideals. Working within the approach of value sensitive design, we sketch how we can capture, formalize and embed a balanced set of values in internet technology as non-functional requirements.Network Architectures and ServicesElectrical Engineering, Mathematics and Computer Scienc

Los materiales del silo n. 146 de Ullastret

Los silos en el poblado ibérico del Puig de Sant Andreu (Ullastret) son muy numerosos, se suelen encontrar formando agrupaciones; esta organización de zonas o campos de silos vendría dada por las cualidades de la roca: en los lugares donde fueron excavados, la formación natural es más blanda. Los silos casi siempre son de perfil ovoideo, planta oval, fondo plano y boca circular, que no acostumbra ser muy regular. El silo n.O 146 se encuentra situado en la parte externa del oppidum, en el sector X - Y, en un campo de silos muy cerca de la muralla; fue excavado durante la Campaña de Excavaciones n.O 19 (1968-1969). El Dr. OLIVA, director de los trabajos arqueológicos realizados en el yacimiento de Ullastret, en su diario de excavaciones manuscrito, que se guarda en el Servei d'Investigacions Arqueologiques de Girana,! describe así el vaciado del silo n.O 146: « ... al norte del 145, ante la muralla ciclópea. En las primeras tierras del margen sur, tocando el muro del silo, aparece una espada de hierro que se hállaba hincada, curvada siguiendo la pared del silo ... Luego salen los cráneos humanos atravesados por un hierro (Croquis en planta del silo) ... La pieza cerámica es la parte inferior de un skyphos en cerámica gris ampuritana, de sección bastante gruesa. Sigue el silo 146 todo quemado hasta el fondo con carbón