Data Distribution Facilities Research Articles

Floodnet: a telenetwork for acquisition, processing and dissemination of earth observation data for monitoring and emergency management of floods

The aim of FLOODNET is to provide a communications and data distribution facility specifically designed to meet the demanding temporal requirements of flood monitoring within the European Union (EU). Currently, remotely sensed data are not fully utilized for flood applications because potential users are not familiar with the procedure for acquiring the data and do not have a defined route for obtaining help in processing and interpreting the data. FLOODNET will identify the potential user groups within the EU and will, by demonstration, education and the use of telematics, increase the awareness of users to the capabilities of earth observation (EO) and the means by which they can acquire EO data. FLOODNET will act as a filter between users and satellite operation planners to help assign priorities for data acquisition against previously agreed criteria. The network will encourage a user community and will facilitate cross-sector information transfer, particularly between ‘flood experts’ and administrative decision makers. The requirement for two levels of flood mapping is identified: (1) a rapid, ‘broad-brush’ approach to assess the general flood situation and identify areas at greatest risk and in need of immediate assistance; (2) a detailed mapping approach, less critical in time, suitable for input to hydrological models or for flood risk evaluation. A likely networking technology is outlined, the basic functionality of a FLOODNET demonstrator is described and some of the economic benefits of the network are identified. © 1997 John Wiley & Sons, Ltd.

Visualization of Distributed Data Structures for High Performance Fortran‐Like Languages

This article motivates the usage of graphics and visualization for efficient utilization of High Performance Fortran′s (HPF′s) data distribution facilities. It proposes a graphical toolkit consisting of exploratory and estimation tools which allow the programmer to navigate through complex distributions and to obtain graphical ratings with respect to load distribution and communication. The toolkit has been implemented in a mapping design and visualization tool which is coupled with a compilation system for the HPF predecessor Vienna Fortran. Since this language covers a superset of HPF′s facilities, the tool may also be used for visualization of HPF data structures.

ISTP science data systems and products

The International Solar-Terrestrial Physics (ISTP) program will provide simultaneous coordinated scientific measurements from most of the major areas of geospace including specific locations on the Earth's surface. This paper describes the comprehensive ISTP ground science data handling system which has been developed to promote optimal mission planning and efficient data processing, analysis and distribution. The essential components of this ground system are the ISTP Central Data Handling Facility (CDHF), the Information Processing Division's Data Distribution Facility (DDF), the ISTP/Global Geospace Science (GGS) Science Planning and Operations Facility (SPOF) and the NASA Data Archive and Distribution Service (NDADS).

Tools for object-oriented SPMD programming

In this paper, we present a new parallel computation model for realistic rendering and 3D simulation applications. Our major goal is to minimize the programmer's work in order to develop, to obtain and to maintain maximal efficiency of this parallel application. To present the framework of our work, we describe the applications we aim at and we explain why object-oriented programming and SPMD (Simple Program Multiple Data i.e. all the processors run the same code in an asynchronous way on different data.) seem to be well suited to the hardware target platform. Then, after a short survey of some existent approaches, we detail our proposition, based on a data distribution facility set offered through a general SPMD programming structure. First, we show how a classical object-oriented language improved by some special concurrent aggregate classes can be sufficient. Then we study how some techniques of virtual communication can efficiently les us manage these features. We end with a discussion as regards implementation problems on our present simulator running on a T800 Transputer network and for the design on a future T9000 Transputer machine.

IRIS—A university consortium for seismology

IRIS is a university consortium organized to provide modernized seismographic networks and data distribution facilities for the university research community and funded by the National Science Foundation (NSF). There are currently 50 member institutions, each of which is represented on the Board of Directors. Overall policy and scientific guidance is provided by this Board acting through a 7‐member Executive Committee and three 9‐member Standing Committees representing each of the program elements. Technical and management support is provided by the President, and a Program Manager or Director for the three operational programs which are 1) Global Seismographic Network (GSN), 2) Portable Array Studies (PASSCAL), and 3) Data Management Center (DMC). This paper presents the historical background of development of IRIS and a review of current operational programs.

SNA Distribution Services

This paper describes the IBM SNA Distribution Services (SNADS). Heretofore, SNA has focused on synchronous data distribution. Along with the advent of office systems and other distributed applications has come the requirement to provide a common architecture for interchanging data asynchronously among diverse systems and products. SNA Distribution Services provides a general asynchronous (delayed delivery) data distribution facility for SNA applications. The initial implementations are for office systems applications. Discussed are objectives for an asynchronous data distribution service, key architectural concepts, the relationship between SNADS and the SNA synchronous communication architecture, and the interface between the distribution service and application transaction programs.