215 research outputs found

    ARC: A Bottom-Up Approach to Negotiated QoS

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    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

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    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

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    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-Ă -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

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    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

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    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

    Interosseous tendon inflammation in the hands of patients with clinically suspect arthralgia: analysis of MRI data from a prospective cohort study

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    Background Inflammation around the tendons of interosseous muscles of the hand (interosseous tendon inflammation) was recently observed with MRI for the first time in patients with rheumatoid arthritis and in at-risk individuals with detectable anti-citrullinated protein antibodies, generating the hypothesis that interosseous tendon inflammation precedes clinical arthritis. To better understand the role of interosseous tendon inflammation during the development of rheumatoid arthritis, we studied the frequency of interosseous tendon inflammation in healthy individuals and in those with arthralgia that was suspected of progressing to rheumatoid arthritis (ie, clinically suspect arthralgia) and the association of interosseous tendon inflammation with other symptoms of inflamed joint tissues and with clinical arthritis development.Methods Adult (age >= 18 years) patients who presented with clinically suspect arthralgia and symptom-free (control) individuals underwent contrast-enhanced hand MRI. MRIs were evaluated for interosseous tendon inflammation on the radial and ulnar sides of the second to fifth metacarpophalangeal joints, and for synovitis, tenosynovitis, and osteitis using the rheumatoid arthritis MRI scoring system. Patients with clinically suspect arthralgia were followed up for clinical arthritis development. The presence of local tenosynovium was examined using immunohistochemistry for anti-CD55 and anti-CD68 on tissue from the hands of three embalmed bodies donated for scientific research. The primary outcome for the cross-sectional part of the study was the presence of interosseous tendon inflammation on MRI. The primary outcome for the longitudinal part of the study was development of clinical arthritis.Findings Between April 3, 2012, and May 20, 2020, 667 patients with clinically suspect arthralgia (mean age 44 years [SD 13], 504 [76%] were women and 163 [24%] were men) underwent contrast-enhanced hand MRI. Between Nov 1, 2013, and Nov 30, 2014, 193 symptom-free controls were recruited (mean age 50 years [SD 16], 136 [70%] were women and 57 [30%] were men). Two (1%) of 193 symptom-free controls had interosseous tendon inflammation. Immunohistochemistry of cadaveric hand tissues showed no tenosynovium surrounding interosseous tendons. At inclusion, 67 (10%) of 667 patients with clinically suspect arthralgia had interosseous tendon inflammation (p<00001 vs symptom-free controls). Interosseous tendon inflammation occurred more frequently if synovitis (odds ratio [OR] 22 [95% CI 12-42]), or tenosynovitis (OR 97 [55-170]), was present at metacarpophalangeal joints. A three-dimensional MRI reconstruction suggested confluency of interosseous tendon inflammation with metacarpophalangeal-flexor-tenosynovitis. 91 (16%) of 558 patients with clinically suspect arthralgia developed clinical arthritis during follow-up (median total follow-up 253 months [95% CI 251-255]). Patients with clinically suspect arthralgia with interosseous tendon inflammation had a higher risk of developing clinical arthritis (hazard ratio [HR] 45 [28-72]), which was attenuated but still significant after adjusting for concomitant synovitis, tenosynovitis, or osteitis (HR 17 [102-28]).Interpretation Interosseous tendon inflammation is almost absent in symptom-free individuals but occurs in people with clinically suspect arthralgia, in whom it correlates with symptoms and is associated with the development of clinical arthritis. The absence of local tenosynovium suggests that interosseous tendon inflammation arises from expanding local subclinical inflammation in the pre-arthritis phase of rheumatoid arthritis.Pathophysiology and treatment of rheumatic disease
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