Showing papers on "Overhead (computing) published in 1974"

A program structure for error detection and recovery

Abstract: The paper describes a method of structuring programs which aids the design and validation of facilities for the detection of and recovery from software errors. Associated with the method is a mechanism for the automatic preservation of restart information at a level of overhead which is believed to be tolerable.

Access control in a relational data base management system by query modification

Abstract: This work describes the access control system being implemented in INGRES (INteractive Graphics and REtrieval System). The scheme can be applied to any relational data base management system and has several advantages over other suggested schemes. These include: a) implementation ease b) small execution time overhead c) powerful and flexible controls d) conceptual simplicity The basic idea utilized is that a user interaction with the data base is modified to an alternate form which is guaranteed to have no access violations. This modification takes place in a high level interaction language. Hence, the processing of a resulting interaction can be accomplished with no further regard for protection. In particular, any procedure calls in the access paths for control purposes, such as in [1,2], are avoided.

Calculating Electrostatic Effects of Overhead Transmission Lines

Abstract: This paper presents an approach to predict ground-level electrostatic effects from overhead power transmission lines using the voltage gradient at ground level Objects like vehicles and animals are represented by Norton equivalent networks The advantages in using this method are 1) accuracy in predicting induced short-circuit current, ?sc, open-circuit voltage, ?oc, and capacitance of object to ground, Cog, and 2) simplicity in needing only simple slide-rule computations that are practical in the field

Material handling apparatus

Abstract: Overhead monorail material handling devices having parts supported by resilient, flexible closed vessels or containers filled with fluid. In some applications a plurality of such vessels or containers are connected by conduit means so that the liquid therein can flow from one to another.

Image transfer sheet material

Abstract: Sheet materials are provided which are useful in preparing negative transparencies for use with overhead projectors Methods for obtaining image transfer and preparation of transparencies are also provided

The Optimum Management of Social Overhead Capital

Abstract: The purposes of this paper are twofold. Firstly, an attempt is made to formulate a theoretical model in which social overhead capital plays a significant role in the processes of resource allocation and in which the distribution of real income is affected by the manner in which the use of such social overhead capital is regulated. Secondly, the pattern of investment in social overhead capital which results in an optimum path of economic growth is examined within the framework of the Ramsey [1] theory of optimum growth.

Swimmer's viewing float

Abstract: A swimmer's viewing float having generally spherical facing upper and lower parts, the latter being transparent and the former having a transparent concave viewing port. The concave shape of the viewing port prevents direct reflection of overhead light by the viewing port surfaces from entering the swimmer's field of view. The field of view is also shielded against reflection of overhead light by the lower part by making the upper part non light transmitting and/or an intermediate masking partition. The float can be rigid or wholly or partially collapsible and air inflatable.

Overhead car washes

Abstract: Overhead frameworks suspending cleaning mechanisms into the paths of cars are supported by pairs of side arches connected rigidly thereto and forming portions of frameworks therewith. In a specific embodiment, the framework is made up of modules, and in another truss-like cross frames suspending cleaning mechanisms are secured to side arches.

Optimal task switching policy for a multilevel storage system

Abstract: Capacity demands for computer memory are increasing. A multilevel storage system provides an economically feasible solution without seriously affecting the total response time. An M-level storage system is considered in this paper. The capability of a digital computer with a multilexel storage system is best enhanced in a multiprogramming environment. In a high level storage system, determination of a best task switching policy becomes an important consideration. In this paper a queuing network is introduced to describe distribution and flow of tasks in the system. An optimal switching policy is determined in relation to the system's overhead time. It is shown that in heavily CPU-limited cases the determination becomes a very simple one; namely, the best policy is given as the threshold level at which the accumulation of the average access time exceeds the overhead time.

Suppression of wake-induced oscillations in a conductor bundle

Abstract: An aerodynamically stable, overhead conductor bundle having spacers located between conductor supporting insulators, the conductors of the bundles being in vertically varying positions relative to one another, between the supporting the insulators. The invention is directed to both structure and method.

A mini-computer network for support of real time research

Abstract: A star-shaped network of mini-computers provides all remote computers access of commonly used peripherals and the University's CDC 6400. The key hardware feature, independent of computer type, is asynchronous serial communication at 153,000 baud with character rate dictated by the receiving computer. Interconnection hardware and software overhead is minimal. The key software feature is the loose connection of near homogeneous machines. Real-time constraints are satisfied by remote computers with idle machines potentially available as a distributed intelligence resource to support additional computer types. Minimal computers may be supported to run unmodified, paper-tape oriented programs using a transparent monitor. Computers with adequate memory may be supported to run mass memory operating systems using Network Central resources. The cost per computer is less than that for paper-tape equipment, while only under heavy load conditions does performance degrade to paper-tape speeds.

Into Community Classrooms: Another Use for Oral History

Abstract: The classroom tape recorder has many advantages but, unfortunately, it is neither as frequently nor as effectively used as movie, slide or overhead projectors. Tapes can be stopped at any time to emphasize important points or to permit instant questioning, replayed to facilitate reexamination or requestioning and arranged or rearranged in any desired manner. And, more importantly, students who cannot or will not read, can, and often will, listen.