2,537 research outputs found

    Multifaceted Distributed Systems Specification Using Processes and Event Synchronization

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    A new approach to modelling distributed systems is presented. It uses sequential processes and event synchronization as the major building blocks and is able to capture the functionality, architecture, scheduling policies, and performance attributes of a distributed system. The approach is meant to provide the foundation for a uniform incremental strategy for verifying both logical and performance properties of distributed systems. In addition, this approach draws together work on performance evaluation, resource allocation, and verification of concurrent processes by reducing some problems from the first two areas to equivalent problems in the third. A language called CSPS (an extension of Hoare\u27s CSP) is used in the illustration of the approach. Employing CSP as a base allows modelled system to be verified using techniques already developed for verifying CSP programs

    Study of fault-tolerant software technology

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    Presented is an overview of the current state of the art of fault-tolerant software and an analysis of quantitative techniques and models developed to assess its impact. It examines research efforts as well as experience gained from commercial application of these techniques. The paper also addresses the computer architecture and design implications on hardware, operating systems and programming languages (including Ada) of using fault-tolerant software in real-time aerospace applications. It concludes that fault-tolerant software has progressed beyond the pure research state. The paper also finds that, although not perfectly matched, newer architectural and language capabilities provide many of the notations and functions needed to effectively and efficiently implement software fault-tolerance

    An inertial motion capture framework for constructing body sensor networks

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    Motion capture is the process of measuring and subsequently reconstructing the movement of an animated object or being in virtual space. Virtual reconstructions of human motion play an important role in numerous application areas such as animation, medical science, ergonomics, etc. While optical motion capture systems are the industry standard, inertial body sensor networks are becoming viable alternatives due to portability, practicality and cost. This thesis presents an innovative inertial motion capture framework for constructing body sensor networks through software environments, smartphones and web technologies. The first component of the framework is a unique inertial motion capture software environment aimed at providing an improved experimentation environment, accompanied by programming scaffolding and a driver development kit, for users interested in studying or engineering body sensor networks. The software environment provides a bespoke 3D engine for kinematic motion visualisations and a set of tools for hardware integration. The software environment is used to develop the hardware behind a prototype motion capture suit focused on low-power consumption and hardware-centricity. Additional inertial measurement units, which are available commercially, are also integrated to demonstrate the functionality the software environment while providing the framework with additional sources for motion data. The smartphone is the most ubiquitous computing technology and its worldwide uptake has prompted many advances in wearable inertial sensing technologies. Smartphones contain gyroscopes, accelerometers and magnetometers, a combination of sensors that is commonly found in inertial measurement units. This thesis presents a mobile application that investigates whether the smartphone is capable of inertial motion capture by constructing a novel omnidirectional body sensor network. This thesis proposes a novel use for web technologies through the development of the Motion Cloud, a repository and gateway for inertial data. Web technologies have the potential to replace motion capture file formats with online repositories and to set a new standard for how motion data is stored. From a single inertial measurement unit to a more complex body sensor network, the proposed architecture is extendable and facilitates the integration of any inertial hardware configuration. The Motion Cloud’s data can be accessed through an application-programming interface or through a web portal that provides users with the functionality for visualising and exporting the motion data

    Dependability investigation of wireless short range embedded systems: hardware platform oriented approach

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    A new direction in short-range wireless applications has appeared in the form of high-speed data communication devices for distances of hundreds meters. Behind these embedded applications, a complex heterogeneous architecture is built. Moreover, these short range communications are introduced into critical applications, where the dependability/reliability is mandatory. Thus, dependability concerns around reliability evaluation become a major challenge in these systems, and pose several questions to answer. Obviously, in such systems, the attribute reliability has to be investigated for various components and at different abstraction levels. In this paper, we discuss the investigation of dependability in wireless short range systems. We present a hardware platform for wireless system dependability analysis as an alternative for the time consuming simulation techniques. The platform is built using several instances of one of the commercial FPGA platforms available on the market place. We describe the different steps of building the wireless hardware platform for short range systems dependability analysis. Then, we show how this HW platform based dependability investigation framework can be a very interactive approach. Based on this platform we introduce a new methodology and a flow to investigate the different parts of system dependability at different abstraction levels. The benefits to use the proposed framework are three fold: first, it takes care of the whole system (HW/SW -digital part, mixed RF part, and wireless part); Second, the hardware platform enables to explore the application’s reliability under real environmental conditions taking into account the effect of the environment threats on the system; And last, the wireless platform built for dependability investigation present a fast investigation approach in comparison with the time consuming co-simulation technique

    Some resonances between Eastern thought and Integral Biomathics in the framework of the WLIMES formalism for modelling living systems

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    Forty-two years ago, Capra published “The Tao of Physics” (Capra, 1975). In this book (page 17) he writes: “The exploration of the atomic and subatomic world in the twentieth century has 
. necessitated a radical revision of many of our basic concepts” and that, unlike ‘classical’ physics, the sub-atomic and quantum “modern physics” shows resonances with Eastern thoughts and “leads us to a view of the world which is very similar to the views held by mystics of all ages and traditions.“ This article stresses an analogous situation in biology with respect to a new theoretical approach for studying living systems, Integral Biomathics (IB), which also exhibits some resonances with Eastern thought. Stepping on earlier research in cybernetics1 and theoretical biology,2 IB has been developed since 2011 by over 100 scientists from a number of disciplines who have been exploring a substantial set of theoretical frameworks. From that effort, the need for a robust core model utilizing advanced mathematics and computation adequate for understanding the behavior of organisms as dynamic wholes was identified. At this end, the authors of this article have proposed WLIMES (Ehresmann and Simeonov, 2012), a formal theory for modeling living systems integrating both the Memory Evolutive Systems (Ehresmann and Vanbremeersch, 2007) and the Wandering Logic Intelligence (Simeonov, 2002b). Its principles will be recalled here with respect to their resonances to Eastern thought
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