67 research outputs found

    The LHCb Hostcard USB interface HUSBi: Project Report

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    The LHCb hostcard USB interface (HUSBi) card is a High Speed USB2.0 communication card used for data interchange and control in high voltage distribution systems for particle detectors at CERN, and particularly in the LHCb experiment. A primary high voltage power supply provides power to the detectors through a network of individual controllers. The HUSBi card is used to link the controllers with host PCs, permitting individual control of all the channels used to supply the detector. The project includes the development of a Linux kernel device driver for the HUSBi communication card. This driver includes a security level that protects the hardware from manipulation that could damage the expensive detector equipment if the high voltage is incorrectly applied. This is done by monitoring each individual channel, and slowly ramping the voltage to the desired level. This thesis includes an overview of the project, with focus on the methods and tools used throughout the course of the project. A description of the knowledge gained from the project is also supplied. Finally, suggestions for improvements or further developments are made

    Using Executable VDM++ Models in an Industrial Application - Self-defense System for Fighter Aircraft

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    When developing complex software systems, one of the most significant challenges is to make sure that the customer and developer agree on the requirements of the system. By using executable models early in the development process, a higher degree of confidence can be gained in the system design and misunderstandings or ambiguous functional requirements can be avoided. This paper presents an industrial case of a communication protocol between two parts of a selfdefense system used on-board fighter aircraft. An executable model of both systems were created using the Vienna Development Method (VDM), and exercised using many scenarios to cover different corner cases. This was done as an alternative to analysing all the scenarios by hand, which would be much more time consuming and far more error prone. The results of the scenario based tests were used to communicate with the customer and ensure that agreement of the requirements was reached

    Development Process for Multi-Disciplinary Embedded Control Systems

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    This report contains the progress report for the qualification exam for Industrial PhD student Sune Wolff. Initial work on describing a development process for multi-disciplinary systems using collaborative modelling and co-simulation is described

    Proceedings of the 9th Overture Workshop

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    This report contains the proceedings of The 9th Overture Workshop, held in Limerick on 20th June 2011

    Multi-domain Modelling in DESTECS and Ptolemy - a Tool Comparison

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    Developing embedded systems with high performance and safety requirements is notoriously hard. It is not enough to have a thorough understanding of the control algorithms used, but a deep understanding of the monitored and controlled physical environment is required to ensure that performance and safety requirements are met. Various tools deal with modeling such multi-domain systems and provide evaluation through simulation. Two such tools — DESTECS and Ptolemy — are examined and compared in this paper, using a case study of an aircraft fuel system. Usability, quantitative, and qualitative comparison criteria are used to give a thorough analysis of the capabilities of the two tools. The contribution of this paper is a description of pros and cons of each tool, helping future users to choose the right tool that suits their needs

    From Lab on a Chip to Point of Care Devices: The Role of Open Source Microcontrollers

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    Microcontrollers are programmable, integrated circuit chips. In the last two decades, their applications to industrial instruments, vehicles, and household appliances have reached the extent that microcontrollers are now the number-one selling electronic chip of all kinds. Simultaneously, the field of lab-on-a-chip research and technology has seen major technological leaps towards sample handling, sample preparation, and sensing for use in molecular diagnostic devices. Yet, the transformation from a laboratory based lab-on-a-chip technology to actual point-of-care device products has largely been limited to a fraction of the foreseen potential. We believe that increased knowledge of the vast possibilities that becomes available with open source microcontrollers, especially when embedded in easy-to-use development environments, such as the Arduino or Raspberry Pi, could potentially solve and even bridge the gap between lab-on-a-chip technology and real-life point of care applications. The profuse availability and extraordinary capabilities of microcontrollers, namely within computation, communication, and networking, combined with easy-to-use development environments, as well as a very active and fast moving community of makers, who are eager to share their knowledge, could potentially be the difference between a dreadful “chip-in-a-lab”-situation, and the next successful start-up. Here follows a brief insight into how open source microcontrollers could potentially have a transformative effect on the field of lab-on-a-chip research and technology. Details in some specific areas of application are briefly treated before addressing challenges and future perspectives

    Synchronous timing of abrupt climate changes during the last glacial period.

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    Abrupt climate changes during the last glacial period have been detected in a global array of palaeoclimate records, but our understanding of their absolute timing and regional synchrony is incomplete. Our compilation of 63 published, independently dated speleothem records shows that abrupt warmings in Greenland were associated with synchronous climate changes across the Asian Monsoon, South American Monsoon, and European-Mediterranean regions that occurred within decades. Together with the demonstration of bipolar synchrony in atmospheric response, this provides independent evidence of synchronous high-latitude-to-tropical coupling of climate changes during these abrupt warmings. Our results provide a globally coherent framework with which to validate model simulations of abrupt climate change and to constrain ice-core chronologies

    Synchronous timing of abrupt climate changes during the last glacial period

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    Many geographically dispersed records from across the globe reveal the occurrence of abrupt climate changes, called interstadial events, during the last glacial period. These events appear to have happened at the same time, but the difficulty of determining absolute dates in many of the records have made that proposition difficult to prove. Corrick et al. present results from 63 precisely dated speleothems that confirm the synchrony of those interstadial events. Their results also provide a tool with which to validate model simulations of abrupt climate change and calibrate other time series such as ice-core chronologies.Science, this issue p. 963Abrupt climate changes during the last glacial period have been detected in a global array of palaeoclimate records, but our understanding of their absolute timing and regional synchrony is incomplete. Our compilation of 63 published, independently dated speleothem records shows that abrupt warmings in Greenland were associated with synchronous climate changes across the Asian Monsoon, South American Monsoon, and European-Mediterranean regions that occurred within decades. Together with the demonstration of bipolar synchrony in atmospheric response, this provides independent evidence of synchronous high-latitude–to-tropical coupling of climate changes during these abrupt warmings. Our results provide a globally coherent framework with which to validate model simulations of abrupt climate change and to constrain ice-core chronologies
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