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Operations Research techniques now provide us with many algorithms for real life routing problems (Bodin 1983; Chapleau 1984; Chapleau 1985). Unfortunately, being often heuristic in nature, their results must be evaluated by hand (by eye would be a more appropriate term). This evaluation must take into account not only the usual constraints (capacity, length, time duration, etc) but also other unwritten ones (overall shape of the route, going back on one self, certain types of vehicle might not be able to go over certain roads, etc). This process usually prompts some more modifications who then in turn must be evaluated.

The exploration of multidimensional data involves the use of a set of empirical techniques which aid in the discovery of interesting avenues to be pursued in later statistical analysis. Data exploration often directs this analysis. The availability and power of computers has changed the nature of statistical work and has made the exploration of multidimensional data more accessible. Graphical methods constitute one of the main tools for data exploration, and they are therefore of primary importance.

This paper describes a software package tailored for the geometric modelling of turbines, as well as for the automatic generation of a body-fitted coordinate grid. The package consists of four programs used respectively for: 1. The creation and the modification of a model; the designer can “edit” the model by means of commands whose basic entities are points, profiles, blades,the hub and the shroud. 2. The refinement of the model by the distribution of points over each profile defining the blade, and then by the interpolation of new intermediate profiles between the hub and the shroud. 3. The construction of surfaces delimiting the blade-to-blade channel boundaries (the computational domain). 4. The calculation of a body-fitted coordinate system, inside the channel, by the solution of a system of differential equations.

Colour is a powerful tool when used to code information on a graphics display, and the growth in the number of colour displays increases the importance of understanding the potential of colour coding.

Fill algorithms are a common graphics utility used to change the colour of regions in the frame buffer. The propagation algorithm is a key component of filling algorithms. The problem of propagation within a fill algorithm is presented and defined, and the difficulties of formalization and comparison are discussed. The previous algorithms are presented and analyzed under a new comparison metric whose validity is confirmed by run-time tests. A new algorithm is developed, and is shown to have better average and worst case behaviour than the others.

Computer programs that allow humans to create pictures are called paint systems. Those that use geometrical shapes as building blocks, rather than brushes, are element-based, rather than canvas-based. The naplps graphics encoding standard, used primarily for videotex, lends itself to the creation of element-based paint systems. The user interface for such a system can be rather complex, because of the need to choose shapes, colours, textures, and the need for editing functions. This paper presents some interface techniques that present the user with a number of easily understood abstractions such as a colour bar, function buttons, and element groups that facilitate the creation of naplps graphics.

This paper addresses the problem of lack of visualization most managers face when using computer-based project control systems: although highly relevant information is generated, usually no graphical output is produced. This paper presents a system called UniPert that automatically produces high quality drawings showing all activities present in a project and the relationship among them. A detailed description of UniPert’s major components and algorithms is presented as well as examples of its actual use. The main contribution of this paper is the integration of many different techniques and concepts that led to the development of the UniPert system.

In the past the simulation of a communication network was usually performed using the batch processing mode. Presented in this paper is a more desirable way to design and evaluate a packet - switched network: the interactive simulation of the network using computer graphics to present the network states over a simulated time interval .

A new digital representation of pictures is proposed. The main feature of this representation is: Given a string of data Z representing a picture with full resolution, various substrings of Z represent the same picture with appropriately lower resolution. This is analogous to a well-known property of holograms. The new representation is based on a particular picture traversal algorithm and uses overlapping sampling areas. The paper presents the principle of this representation, analyzes its overhead, and provides examples of picture reconstruction. An application of the hologram-like representation to the transmission of pictures with progressive resolution is indicated.

This paper describes an innovative user interface for a general purpose computer-aided design system. It is being developed as part of an investigation into distributed processing in manufacturing environments The system supports three-dimensional design capabilities for execution locally and incorporates model compatibility for communication with mainframe CAD systems.