1,721,125 research outputs found
Experiences with the TinyOS Communication Library
No full textTinyOS is a useful resource for developers of sensor networks. The
operating system includes ready-made software components that enable rapid
generation of complex software architectures. In this paper we describe the lessons
gained from programming with the TinyOS communication library. In particular,
we try to rationalize existing functionalities, and we present our solutions in the
form of a communication library, called TComm-Lib
A framework for FMI-based co-simulation of human–machine interfaces
No full textA framework for co-simulation of human–machine interfaces in Cyber-Physical Systems (CPS) is presented. The framework builds on formal (i.e. mathematical) methods. It aims to support the work of formal methods experts in charge of modelling and analysing safety-critical aspects of user interfaces in CPS. To carry out these modelling and analysis activities, formal methods experts usually need to engage with domain experts that may not fully understand the mathematical details of formal analysis results. The framework presented in this work mitigates this communication barrier by allowing formal methods experts to create interactive prototypes driven by formal models. The prototypes closely resemble the visual appearance of the system being developed. They can be used to discuss details of the formal analysis effort without showing any mathematical detail. An existing prototyping toolkit based on formal methods is used as baseline technology. Novel functionalities are developed for automatic generation of interactive prototypes supporting the Functional Mockup Interface (FMI), a de-facto standard technology for simulation of complex systems. Using the FMI interface, the prototypes can be integrated with simulations of other system components. The architecture of the framework is presented, along with a verification of core aspects of its functionalities. A case study based on a medical system is used to demonstrate the capabilities of the framework
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Rare presentation of asymptomatic pericardial effusion: Hemangioma of the atrioventricular groove in cardiac magnetic resonance imaging
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A Tool for Checking Secure Interaction in Java Cards
No full textWe present an approach based on a multilevel security policy and the theory of abstract interpretation for checking secure interaction between applications in Java Cards. The security policy is defined by the user, which assigns security levels to Java Card applications. Actual values are abstracted into security levels, and an abstract interpreter executes the bytecode of applications in the abstract domain. We show JCSI, a tool that implements the presented approach. JCSI can be used to check the binary code of Java Card applications before their installation on-card
An application adaptation layer for wireless sensor networks
No full textIn wireless sensor networks, poor performance or unexpected behavior may be experienced for several reasons, such as trivial deterioration of sensing hardware, unsatisfactory implementation of application logic, or mutated network conditions. This leads to the necessity of changing the application behavior after the network has been deployed. Such flexibility is still an open issue as it can be achieved either at the expense of significant energy consumption or through software complexity. This paper describes an approach to adapt the behavior of running applications by intercepting the calls made to the operating system services and changing their effects at run-time. Customization is obtained through small fragments of interpreted bytecode, called adaptlets, injected into the network by the base station. Differently from other approaches, where the entire application is interpreted, adaptlets are tied only to specific services, while the bulk of the application is still written in native code. This makes our system able to preserve the compactness and efficiency of native code and to have little impact on the overall application performance. Also, applications must not be rewritten because the operating system interfaces are unaffected. The adaptation layer has been implemented in the context of TinyOS using an instruction set inspired to the Java bytecode. Examples that illustrate the programming of the adaptation layer are presented together with their experimental validatio
Correspondence: Letter by barison et al regarding article, "cardiac magnetic resonance postcontrast t1 time is associated with outcome in patients with heart failure and preserved ejection fraction"
No full textEnergy-efficient reception of large preambles in MAC protocols for wireless sensor networks
No full textA technique able to significantly reduce the energy consumption of contention-based MAC protocols for wireless sensor networks is presented. Address and timing information is embedded into the packet preamble, allowing receivers to power off their radio during part of the transmission. Analytical and experimental evaluations show a significant extension of the network lifetime
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