ARC: A Bottom-Up Approach to Negotiated QoS

Mobile systems operate in a resource-scarce environment and thus must adapt to external conditions; all layers must make cost-based decisions about what mode of operation to use in response to performance feedback. This paper focuses on the generic interface between adjacent layers (client and server) in a multi-level hierarchy. The Adaptive Research Contracts (ARC) framework uses a bottom-up approach in which the server exposes a range of quality/cost modes to the client above. This allows the client to trade off various algorithms generating different workloads for multiple resources. A case study shows that control can be distributed effectively over multiple layers with ARC; global cost-effective solutions can be obtained by exchanging a small fraction of all possible control settings

Application Interaction Model for Opportunistic Networking

In Opportunistic Networks, autonomous nodes discover, assess and potentially seize opportunities for communication and distributed processing whenever these emerge. In this paper, we consider prerequisites for a successful implementation of such a way of processing in networks that consist mainly of heterogeneous devices. Devices are heterogeneous in size, in abilities, in movement, and in the role they play in the application. The focus here is on the interaction at different levels and among various nodes, in view of our current scenario, where mobile nodes connect clusters of wireless sensors. The combined networks form an infrastructure-less sensor and actuation network. We propose a RESTful interaction model, which we demonstrate with an example implementation

Pentecostalism and the arts of insistence: examples from Botswana

This contribution explores the significance of religious practices that put emphasis on encouraging people to hold their position when others question the ideological or dogmatic elements of their faith. Applying the term ‘religious insistence’, it investigates these practices with a view to the ways in which Pentecostals take a position vis-à-vis the challenges they confront in the sociopolitical domain. Contributing to the study of religious activism, we show that practices of insistence are neither fully resistant nor fully acquiescent with regard to the existing situation. We argue that these practices of holding one’s ground, which we subsume under the term ‘insistence’, represent a specific modality of formulating one’s identity in regard to others that is neither about provoking structural change, as a resistance perspective would emphasise, nor about condoning a structural situation as is and remaining fully acquiescent with it. While in Pentecostal contexts insistence does not take up-front political protest as its main focus, it can still be interpreted as a form of religious activism since it often entails some form of critical response toward a given sociopolitical order or process. By drawing attention to how religious insistence manifests itself in and through Pentecostalism, this contribution proposes to enrich the study of religious activism in Africa and opens up a perspective that addresses assertiveness as a register of expression that differs from resistance and acquiescence.ASC – Publicaties niet-programma gebonde

Reuse of pervasive system architectures

Developers are often confronted with incompatible systems and lack a proper system abstraction that allows easy integration of various hardware and software components. To try solve these shortcomings, building blocks are identified at different levels of detail in today’s pervasive/communication systems and used in a conceptual reasoning framework allowing easy comparison and combination. The generality of the conceptual framework is validated by decomposing a selection of pervasive systems into models of these building blocks and integrating these models to create improved ones. Additionally, the required properties of pervasive systems on scalability, efficiency, degree of pervasiveness, and maintainability are analysed for a number of application areas. The pervasive systems are compared on these properties. Observations are made, and weak points in the analysed pervasive systems are identified. Furthermore, we provide a set of recommendations as a guideline towards flexible architectures that make pervasive systems usable in a variety of applications

Open Home Networks: the TEAHA Approach

The current trend for home appliances is networking. Although more and more of these appliances are networked, there is not a standard way of interaction, which restrains the development of services for in-home networks. The lack of standardisation is partly due to a legacy of business interests; white goods, audio video equipment, security, and personal digital appliances all have a different background and have different business models. Rather than profound standardisation we propose secure seamless interworking of technologies, applications, and business interests. In this paper we present an architecture which is embedded in legacy technology. Our approach combines known design patterns, augments existing technology, and facilitates so-called business clusters. Further, we discuss a prototype implementation that integrates as an example OSGI, ZIGBEE, and UPNP technology with CECED (white goods) business interests. The work reported in this paper has been executed in an international industrial project: TEAHA

Predicting health-related quality of life in dialysis patients: factors related to negative outcome expectancies and social support

Health and self-regulatio

The value of inquiring about functional impairments for early identification of inflammatory arthritis: A large cross-sectional derivation and validation study from the Netherlands

Objectives Healthcare professionals other than rheumatologists experience difficulties in detecting early inflammatory arthritis (IA) by joint examination. Self-reported symptoms are increasingly considered as helpful and could be incorporated in online tools to assist healthcare professionals, but first their discriminative ability must be assessed. As part of this effort, we evaluated whether inquiring about functional impairments could aid early IA identification. Design Cross-sectional derivation and validation study. Setting Data from two Early Arthritis Recognition Clinics (EARC) in the Netherlands were studied, which are easy access outpatient rheumatology clinics intermediary between primary and secondary care for patients in whom general practitioners suspect but are unsure about IA presence. Participants Between 2010 and 2014, 997 patients consecutively visited the Leiden-EARC (derivation cohort). Patients c