Showing papers on "Data flow diagram published in 1974"

A preliminary architecture for a basic data-flow processor

Abstract: A processor is described which can achieve highly parallel execution of programs represented in data-flow form. The language implemented incorporates conditional and iteration mechanisms, and the processor is a step toward a practical data-flow processor for a Fortran-level data-flow language. The processor has a unique architecture which avoids the problems of processor switching and memory/processor interconnecion that usually limit the degree of realizable concurrent processing. The architecture offers an unusual solution to the problem of structuring and managing a two-level memory system.

A computer architecture for highly parallel signal processing

Abstract: A computer of unusual architecture is described that achieves highly parallel operation through use of a data-flow program representation. The machine is especially suited for signal processing computations such as waveform generation, modulation, and filtering, in which a group of operations must be performed once for each sample of the signals being processed. The difficulties of processor switching and memory/processor interconnection arising in attempts to adapt Von Neuman type computers for parallel operation are avoided by an organization in which sections of the machine communicate through transmission of information packets, and delays in packet transmission do not compromise effective utilization of the hardware. The design concept is especially suited to implementation using asynchronous logic and large-scale integrated circuits. Application of the concepts to generalized data-flow program languages is under study.

Application of Computer-Aided Aircraft Design in aMultidisciplinary Environment

Abstract: Applications of a multidisciplinary system of computer programs to selected analytical and optimization problems encountered in an aircraft design are described The depth of the analyses and optimizations permits such detailed output as individual stringer sizes and pressure distributions Data flow from one program to another is performed in a hands-off manner in the modular and open-ended system Numerical examples show how this automation permits multidisciplinary trade-off studies, typical of a preliminary design process to be based on such a level of detail in each discipline that normally would not be available at this stage of the process

Interprocedural Analysis and the Information derived by it

Abstract: Well structured programs are usually expressed as a system of functionally oriented procedures. By analyzing and transforming an entire system of procedures, linkages can be modified or eliminated and interprocedural data dependencies documented to the user. This paper presents some of the methods being developed to effect such interprocedural analysis and transformations.

A synopsis of Seasat-A scientific contributions

Abstract: SEASAT-A satellite data processing and modelling capabilities address scientific and applications problems in the domains of oceanic, atmospheric, and solid earth geophysics studies by the use of active radar, and passive microwave and infrared instruments. A data flow map depicts the interrelationship between SEASAT-A instruments and other sources of information and the geophysical parameters to be determined.

Semantic Characterization of Flow Diagrams and Their Decomposability

Abstract: Structured Programming has raised much attention to the problem of program schemata (flow diagrams) decomposability. In fact, the possibi lity of writing a program, in a top-down fashion, i.e. by successive refiniments of its parts, and the possibility of considering a program as consisting of subprograms, depend also on the possibility of identi fying within a flow diagram some elementary control structures which constitute its components.

The architecture of the picture system

Abstract: THE PICTURE SYSTEM is a self-contained, stand-alone line drawing system for presenting dynamically moving pictures of two- or three-dimensional objects. This highly interactive system can display smoothly changing true perspective views of 3-D objects in real time. Objects can be rotating, translating, and changing in scale. Individual sub-objects can assume independent or compound motion. Lines or parts of lines outside the chosen viewing window are clipped. All these transformations are performed digitally to avoid inaccuracy and range limitations.In order to perform these calculations fast enough to show smooth motion, support high-level interaction, and also sustain flicker-free pictures of 11000 line segments or more, a new graphics system architecture has been developed. This paper will present each of the hardware components of the system and discuss what each contributes to the production of pictures.THE PICTURE SYSTEM represents a significant new graphics system architecture in several respects. This paper will describe the system including data flow, the functions of each major component, and some of the advantages that accrue from the approaches taken.

An algebraic approach to data organization

Abstract: The paper is concerned with a formal treatment of data structures. The introduction outlines the main features of Generalized Data Base Management Systems and gives the general diagram of information flow in such a system. Section 1 is concerned with the structuring of data on levels. For a given real object setB, the levels of data representation as item, record, and file are discussed and the structure of the levels is characterized. In section 2 a basic algorithm for file search is given. To characterize the file data structure, the concept of directory is defined. A conventional example closes this section. In section 3 the concepts of data base and subdata base are defined as next level of data organization, and the access algorithms to such data structures are described.