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[en] The implementation of a modern game-console controller as a data acquisition interface for physics experiments is discussed. The investigated controller is equipped with three perpendicular accelerometers and a built-in infrared camera to evaluate its own relative position. A pendulum experiment is realized as a demonstration of the proposed approach
[en] Employment of a data-acquisition system for data collection and calculations makes experiments with antennas more convenient and less time consuming. The determined directional patterns of the dipole antennas of different lengths are in reasonable agreement with theory. The enhancement of the signal by using a reflector is demonstrated, and a variant of the Yagi-Uda antenna is explored. The experiments are suitable as laboratory works and classroom demonstrations, and are attractive for student projects.
[en] A programme has begun on MAST to replace its ageing CAMAC and VME based data acquisition systems with new modern hardware which, together with several improvements in the supporting infrastructure, will provide support for faster data acquisition rates, longer-pulse operation, faster data access and higher reliability. The main principle of the upgrade was to use commercial off-the-shelf (COTS) hardware and well-established standards wherever possible. CompactPCI or PXI was chosen as the digitiser form factor to replace CAMAC/VME, and Ethernet would be used as the means to access all devices. The modular architecture of the MAST data acquisition software framework has helped to minimise the integration effort required to phase in new subsystems and/or new technologies whilst continuing to use the old hardware in other systems. The software framework was updated to allow more versatile use of the network-attached data acquisition devices. The new data acquisition devices had multiple connector types, which created difficulties with the cable interfacing. To resolve this and provide support for easy substitution, a standard connector interface was chosen, based on the most common connector type and pin-out already in use, and several cable assemblies were produced to connect the proprietary interface of the digitiser to the standard interface block. The in-house IDA-3 data storage format is unable to accommodate the larger file sizes and is increasingly difficult to maintain, so it is to be gradually phased out. The NetCDF-4/HDF5 data standard is being adopted as its replacement, thus reducing in-house maintenance whilst providing a data format that is more accessible to the Fusion community. Several other infrastructure upgrades were necessitated by the anticipated increase in data traffic and volume including the Central Timing System, the MAST Ethernet infrastructure and servers for front-end data processing, data storage and data access management. These improvements have provided higher reliability, faster data retrieval, greater longevity and capacity to extend the MAST pulse length to accommodate the future programme requirements.
[en] MDSplus is a data acquisition system widely used in nuclear fusion experiments. It defines a file format for pulse files and provides a set of tools for data acquisition and management. The whole MDSplus package is used in several fusion experiments to set-up and supervise the data acquisition process. Other experiments use only the data management layer of MDSplus to provide a common format for data exchange between plasma fusion laboratories. HDF5 is a file format and a data access library used by a larger community, mainly outside fusion. HDF5 is used, for example, in earth science research, defense applications and weather services. HDF5 allows managing large and complex data sets and provides a common data format among heterogeneous applications. Both MDSplus and HDF5 support a rich set of data types and a hierarchical data organization, as well as multi-language data access libraries. There are however several significant differences between the two system architectures, making each system better suited in different application contexts. The paper provides a brief overview of the data architectures of MDSplus and HDF5 and analyzes more in detail the peculiar aspects of the two systems. It will be shown that the ranges of applications suitable for the two systems overlap only partially. Finally, some application scenarios will be presented, discussing to what extent each system can provide an optimal solution. This document is composed of an abstract and a poster. (author)
[en] The Pilot library is targeted to novice scientific programmers within High Performance Computing. The CellPilot library extends the Pilot library to the Cell Broadband Engine processor and heterogeneous clusters. Using Pilot's process and channel abstractions, the CellPilot library can create a process on any of the processor types, both PPEs and SPEs, across the cluster. Communication is achieved by creating a channel between any two processes, and using the write/read channel functions in the participating processes. The CellPilot library uses MPI for the inter-node communication and the Cell SDK within a Cell node. All the architecture specific details of Cell communications are hidden from the user.
[en] This paper presents the extension of the data acquisition and control system JDAQ, used at TEXTOR, to allow different data acquisition hardware. The extension was developed for the INCAA-TR10 and INCAA-TR32 recorders. These modules are built in the 'CompactPCI' hardware format. It has been demonstrated that measuring with PCI modules under JDAQ is possible. However, the handling of the modules is not as systematic as measuring with CAMAC modules. General problems with implementation of the PCI modules will be discussed in this paper.
[en] As in any other long-lasting experiment, new and standard activities on Frascati Tokamak Upgrade may require technological updates, especially on the control and data acquisition domain. The present paper will deal with a set of experiences arising from the necessity to replace ageing systems that turned out to be an interesting test-bed for new technologies. The first case study deals with FTU slow control, which is based on a standard three-layer model. The lower layer has been updated in the G1 power supply of the toroidal field, replacing the old Westinghouse PLC with a Siemens-S7. To integrate the new PLC in FTU control system, the open source LibNodave package under Linux operating system has been used. The results are compared to those obtained using the Siemens-S7 commercial library. The second case study regards FTU magnetic measurements. The system proposed will lead to the replacement of the old CAMAC system with a PXI embedded controller, acquiring hundreds of signals. Finally it will be shown how, taking advantage of those technologies, an ITER relevant control and data acquisition architecture can be designed.
[en] A common moving-coil loudspeaker is useful for learning harmonic motion. A simple optical method is used to observe free and forced oscillations of the diaphragm of a loudspeaker. With a lock-in amplifier and data-acquisition system, the frequency response of the loudspeaker and its electrical impedance are automatically recorded versus frequency. From the measurements, it is easy to calculate electrical and mechanical parameters of the loudspeaker
[en] Full text of publication follows: The CODAS management systems which are in place to support JET operations and JET enhancements will be described. UKAEA Culham gained accreditation to Iso 9001:2000 in June 2003. The 2000 standard emphasises the identification of processes within an organisation, the interaction between processes, via inputs and outputs, and the measurement of their effectiveness allowing continual improvement. Process maps are ideal for documenting the processes. Within CODAS a set of web-based process maps have been developed. These have been layered over existing procedures and database systems and under the UKAEA Culham-wide process maps. Some of the CODAS process maps pertaining to operations and enhancements will be described and their usefulness will be discussed. The inputs and outputs from the processes often correspond to database records, not necessarily in the same logical or physical systems. The interaction between the processes then involves integrating different databases. 'Joining-up' legacy database systems may not be trivial, thus emphasizing the requirement for an integrated data model and centralized database management across the organisation. This problem will be illustrated using the example of the 'list of JET diagnostics' in various systems and conclusions for ITER will be drawn. (authors)
[en] The ngdp framework advanced topics are described. Namely, we consider work with CAMAC hardware, 'selfflow' nodes for the data acquisition systems with the As-Soon-As-Possible policy, ngmm(4) as an alternative to ngsocket(4), the control subsystem, user context utilities, events representation for the ROOT package, test and debug nodes, possible advancements for netgraph(4), etc. It is shown that the ngdp is suitable for building lightweight DAQ systems to handle CAMAC