User Desires Research Articles

Cognitive models and information transfer

Information transfer (or the information ‘system’) can be considered as the dynamic interaction among three components: the user; the knowledge resource; and the intermediary mechanism between the first two components. The knowledge resource contains texts (in the semiotic sense), represented and organized in some way. The user initiates the system because of some problem, goals, intentions, etc., whose management or realization s/he believes might be furthered by information obtained from the knowledge resource. The intermediary mechanism mediates between the user's desires, requirements, knowledge, etc., and the knowledge resource's contents, representation and organization, so that if texts appropriate to the user's situation are in the knowledge resource, they (or aspects of them) are brought to the user's attention. Here we concentrate upon the intermediary function: why it is necessary; why it is problematic; what its important features are; how it might be improved. The overall approach is based on the idea of cognitive models or images that the components of the system have of one another and of themselves. Specifically we will be concerned with the intermediary's role in building up its own model of the user in interaction with the user, in order both to help the user in clarifying the problem and to develop a representation of that problem which it judges likely to obtain useful responses from the knowledge resource. There will be some theoretical discussion, based on the ASK hypothesis and related work, but the primary method will be analysis of real human/human information-related dialogues. The foci of attention will be the functions carried out in such dialogues and how they are carried out, and the central role of interaction between user and intermediary in cognitive model construction which leads to successful system performance.

Application of a new algebraic manipulator theory

We have developed a new algebraic manipulator at the Naval Observatory, for application to lunar and planetary theories. The manipulator is quite general in that it is written in IBM FORTRAN IV language, but otherwise is independent of the bit and word structure of any particular computer. If the user desires, the number of polynomial and trigonometric arguments may be varied without limit. The math and order subroutines use an efficient one-to-one core mapping process. A higher level set of operation codes to simplify programming is built in. For example, the problemh=[(ab)/(cd)]1/2, wherea, b, c, d are series, is computed by the statement: CALL EXPR (H, ‘*’,A, B, ‘*’,C, D, ‘DV’, $1, $2, ‘R’, $3, ‘=’).

PREFERENCES FOR ALLOCATING RIVER RECREATION USE1

ABSTRACTAllocating river recreation use to commercial and private sectors on white water rivers has been highly controversial. How this process is implemented may affect not only the availability of recreation opportunities to individual users, but may also negatively impact the user's desire to escape from the pressures and stresses of everyday life. In a study of users of Idaho's Middle Fork of the Salmon River, an Even‐Pool allotment technique was preferred over others by the commercial, private, and rejectee individuals sampled. A lottery technique for rationing private use permits was preferred by private users and rejectees, while commercial users preferred Advance Reservation. No relationship was found between the users' stress release/escape expectations and their preferences for the different allotment and rationing techniques studies. Such results suggest that river managers may have considerable latitude in selecting allocation techniques that do not adversely affect on‐site recreation experiences.

Is EURONET C.C.L. a ‘common’ command language?

Since the availability of EURONET DIANE at the beginning of 1980, users are confronted with the EURONET Common Command Language. The strong desire of users to practice only one retrieval language should be fulfilled as the creators of the network developed one command language, the EURONET C.C.L. Until now about five of the service providers have implemented the C.C.L. and it is highly desirable that other services will follow soon as the harmonisation of retrieval languages obviates the need for the users to converse in different command languages.

QUADRIL

Most man-made objects can be closely approximated by bodies whose surfaces are composed of portions of second-order (quadric) surfaces. These surfaces include elliptic, hyperbolic, and parabolic cylinders, as well as quadric cones, paraboloids, hyperboloids, ellipsoids, and pairs of planes. Simple planes (first-order surfaces) may be included as degenerate quadric surfaces. Because these quadric-surface bodies are so useful for modelling man-made objects, it is important that any Computer-Aided Design (CAD) system be able to work with such bodies. The “QUADRIL” language described here was designed to accept descriptions of quadric-surface bodies in character-string form. QUADRIL has a mixture of English-like and algebraic syntax. It may be used to specify quadric-surface bodies and then to display them on various media. QUADRIL will accept descriptions of quadric-surface bodies either as “volumetric” combinations of basic bodies, or as boolean functions of bounding surfaces. English-like syntax is used for specifying what surfaces and basic bodies are used, while algebraic syntax is used to transform the canonical forms of the surfaces or bodies into the shape, position, and orientation that the user desires. Volumetric combination of bodies involves the operations of union (+), intersection (*), and subtraction (-). Boolean specification of volumes is in terms of a boolean tree with the bounding surfaces as leaf nodes. The tree is expressed as a character string. QUADRIL permits using user-created “STRUCTURES” as component bodies (“OBJECTS”) in greater STRUCTURES. The display of the quadric-surface bodies may also be specified in QUADRIL. The user is considered fixed in space, while the body is transformed to give the desired view.

Maximizing coefficient alpha reliability while maintaining validity

Maximizing coefficient alpha reliability while maintaining validity

Civil Marine Applications of the Global Positioning System

When considering what to write about civil marine applications of the Global Positioning System (GPS), the first thought was to review all of the diverse marine navigation requirements and show to what extent GPS could be used for each. The problem with this concept is that GPS will be nearly a universal navigation aid. Except for applications requiring underwater operation or sub-meter measurement precision, GPS will be able to do practically everything else! Therefore, a different approach has been taken. First, GPS is defined for the marine operator. The intent is to show its inherent capabilities, partly by contract with some of today's navigation systems. Following this is an attempt to express the natural desire of marine users for the system to be implemented and operated in a way to serve them best. It is suggested that civil users should be represented by a civil government agency during system development and as a point of contact for liasion after GPS becomes operational. The need for civil access to the best possible accuracy performance also is stressed. Factors affecting the price of GPS civil user equipment are considered, followed by a discusion of whether proposed signal structure changes intended to reduce the cost of civil equipment should be considered at this time. Overall, the paper celebrates the potential offered by GPS and urges that the system evolve so as to maximize benefits to a wide variety of civil users.

The past, present, and future of minicomputers: A scenario

This article traces the evolution of minicomputers from 1955 to 1973 and forecasts their near-future characteristics and uses. Advances significant in the growth of minicomputers are tutorially described as they occurred in nineteen different machines. Only computers having attained the status commercially available are included. The entire discussion is based on two descriptors: the first, depicting the content and use of minicomputer systems (hardware, software, applications, and tradeoffs); and the second, outlining the size and type of systems (simple, complex, general-purpose, and special-purpose). Future minicomputers will continue to diversify in the four general directions indicated by the size-type descriptor. By superimposing the user desires for easier programming, better performance, and lower cost onto the size-type descriptor, the article concludes with a description of future systems.

User Desires and Graphics Capability in the Academic Environment

AbstractThis paper is an attempt to determine the average geography academic's needs in relation to his research requirements and computing knowledge in automated map production. Usually he will not be attempting to produce a final map, but probably only one to enable him to analyse his data with more accuracy. An outline is given of what the user can expect from a plotting system, and also what he will have to know to benefit from the results produced. The problem of contouring is taken as a demonstration of the difficulties involved. Examples are given to show that no computer contour map can be considered objective, and that the results produced are determined by the contouring method employed combined with the skill of the user.

User Desires and Graphics Capability in the Academic Environment

User Desires and Graphics Capability in the Academic Environment

Computer-aided thermal analysis of power semiconductor devices

Thermal analysis of power semiconductor devices is often complicated by odd geometries and the nonlinear properties of materials. It is the type of problem that can best be handled by a computer. Fortunately, numerous general-purpose heat transfer programs have been written that can be applied to power semiconductor deyices. The majority of programs were written for other technologies (aircraft engines, nuclear energy, and space) but they are sufficiently general for electronic applications. These programs are most often based on the method of finite differences. While this method can yield results to any degree of accuracy required, it is not readily apparent just how accurate the results are. In general, a user desires results as accurate as necessary while minimizing the cost of the problem solution. This paper deals with methods of achieving that goal. Descriptions of truncation and convergence errors are given along with methods of estimating their magnitude. Various forms of the finite difference method are discussed. Methods for speeding convergence are shown, including acceleration algorithms and simple guidelines for ordering matrices and selecting node boundaries. Convenient methods of displaying and interpreting the results are also discussed.