Abstract: This paper proposes several latent structure models for the analysis of mobility tables and examines the relationship of these to some earlier mobility models (e.g., the "perfect" and the "quasi-perfect" mobility models). Data from the classic Danish (5 X 5) and British (5 X 5 and 8 X 8) mobility tables are used to illustrate the utility of these methods in comparative analysis. A model designated as a quasi-latent structure is suggested as a plausible rendering of the structure of mobility for each set of data, and this model is used to derive various kinds of substantive inferences.

Abstract: A process and apparatus for rendering visible an electrostatic charge image. The visible image is formed on the surface of a liquid by positioning a charge image adjacent the liquid at distances of about 10 to 1,000 μm from the surface of the liquid without contacting the liquid.

Abstract: A laser photocoagulator 10, comprises a fibre optic guide 13 one end of which is accommodated by an endoscope 14 and the other end of which has a coupling 18 for connection to a laser 11 and a gas supply 12. Launch optics 32 are accurately located in coupling 18 with respect to end 34A of optical fibre 34 which traverses the length of the guide 13 thereby rendering the guide replaceable without dislocation of the endoscope 14, the laser 11 and the gas supply 12. The coupling 18 comprises separate clamp means for the optical fibre 34 and the optics 32 enabling accurate alignment co-axially and spatially so that the laser output is focussed on the free end 34A of the fibre 34 without any requirement to align the laser 11 accurately with optics 32.

Abstract: L'appareil est constitue d'au moins un support amovible (102), un second moyen de traitement de l'information (115), un troisieme moyen de dialogue bidirectionnel (103) entre le support amovible (102) et le second moyen de traitement de l'information (115), un quatrieme moyen de delivrance du service (116). The apparatus consists of at least one removable medium (102), a second information processing means (115), a third way to two-way dialogue (103) between the removable medium (102) and the second means processing information (115), a fourth means of delivery of the service (116). Le support amovible comprend des moyens de connection, des moyens de traitement de l'information, des moyens de memorisation et des moyens de decision, des moyens de dialogue bidirectionnels. The removable support comprises connection means, to information processing means, memory means and decision means, bidirectional dialogue means. Application : Appareils de distribution de billets de banques ou de services. Application: bank cash dispensing devices or services.

Abstract: As previously demonstrated by Badler and O'Rourke, a variety of 3-D objects can be defined conveniently as collections of spheres-having various sizes and positions in 3-D space and possibly intersecting. This paper is an elaboration on the technique, describing methods of constructing and manipulating such objects and, most particularly, a method of achieving realism in rendering the picture-even though, for reasons of efficiency, computation is performed as if everything were 2-dimensional, with depth ordering.Pictorial realism results from three features of the overall method: roundedness of the basic picture plane images of individual spheres, pictorial merging of 3-dimensionally intersecting spheres (which are very likely intended as parts of the same object), and pictorial separation of spheres whose images overlap but which lie at significantly different depths in 3-space. Separation is achieved by a black line and resembles the lines traditionally found in cartoon cel animation; merging is accomplished by arranging, in effect, for every sphere image to be transparent to the brighter parts of images of other spheres of the same color.The system lends itself well to construction and manipulation of objects defined by geometry and mathematical transformations; it also serves well in construction and depiction of organic forms which arise and/or are modified by random growth and rules of contingency. Several examples of pictorial results are presented.

Abstract: VLSI (very large-scale integration) technology provides and demands new ways of solving large-scale computational problems. A pipelined version of a real-time hidden surface elimination algorithm is proposed. The approach is tuned to the requirements of the VLSI technology: it is simple and regular, employs only local communication, and attains a high degree of parallelism. The feasibility of the technique is demonstrated for a computer graphics system where objects are defined in terms of planar triangular surface elements. A case is made in terms of early 1980s technology. The use of VLSI will make high-power graphics available to the small user as well as the traditional flight simulator customer. This is achieved by enabling system expansion to take place through the addition of more identical chips. Consequently system cost is linear with respect to the number of chips used, a number determined by the maximum number of rendering elements needed by the specific user application.

Abstract: In 1965, Shepard introduced a general interpolation formula for arbitrarily spaced data over any finite dimensional Euclidean space. The deficiencies in his initial results have been corrected and later derivations have been widely applied to surface fitting problems in aviation design and geology.This paper describes a new research direction in Shepard's method and a new application to computer graphics. In the first, the convex weighting functions are generalized by the creation of a user-defined mathematical domain which is independent of the surface. In the second, the original formula is applied to blend mapping projections for aviation visual simulation and an algorithm for rapid evaluation is presented.

Abstract: Scholarly opinion on the quality of the architectural drawings of Villard de Honnecourt in his famous manuscript in Paris (Bib. Nat., ms. fr. 19093) varies widely.1 Yet there is general agreement hat Villard was, whatever his other deficiencies as a draftsman, most skilled at rendering drapery.9 Active between ca. 1220 and ca. 1240, Villard was a Picard artist who practiced that treatment of drapery now termed muldenfaltenstil which was widely employed in manuscript painting, metalwork, stone sculpture, and stained glass in northern France in the early thirteenth century (Figs. 1-4).3 This drapery-treatment is characterized by tightly curved loops referred to as hair-pin or pot-hook loops which by form and frequency create a rich and restless pattern regardless of the medium in which they are found. For all the published commentary on Villard's artistic style, there has been very little published analysis of his artistic technique, and most of that has been superficial.4 Most commentators imply note that he made preliminary sketches in leadpoint or in silverpoint which he sometimes later inked.5 The key word here is \"sometimes,\" because the little noted fact is that Villard left his drawings in various stages of completion from preliminary sketched outline to finished inked rendering. Analysis of these stages of building up a finished drapery rendering reveals that Villard's technique was more than a simple two-step process. This is of interest as demonstrating the working procedures of a thirteenth-century draftsman. It is of still greater interest because Villard's technique provides the key to his training, and possibly to his profession, as an artist-craftsman . Analysis of Villard's drawings is of course best made through examination of the manuscript itself, for the subtleties involved reproduce poorly in photographs, including those accompanying this article. But it is possible to follow the process by studying photographic reproductions if one keeps in mind that the contrasts between leadpoint sketches and inked reinforcements are not nearly so harsh in the original drawings as they appear to be in reproductions. To complete a drapery rendering, Villard went through a six-step process. The first was to make a light, preliminary leadpoint sketch on the parchment. This sketch could be corrected or modified by rubbing and/or redrawing until Villard obtained the result he desired.6 One of the clearest examples of this in the manuscript is the right foot of a seated king on fol. 25r (Fig. 5),7 where it is evident that Villard had considerable difficulty achieving satisfactory perspective and/or proportion in this particular detail. It is not possible to be absolutely certain, but to judge from the steps which followed, Villard apparently drew outlines or contours of entire figures before committing himself to any detailing within the areas defined by his contours. The figures on fol. 25v of the manuscript demonstrate the next several steps in Villard's drawing process (Fig. 6).8 When he had completed the leadpoint contour, he then sketched in the drapery folds and pleats lightly in leadpoint without applying any shading or shadowing. When this was achieved, he then employed a brush and a very pale red-sepia ink wash to reinforce the contour line he wished to preserve. This inking was not, however, employed within the contours to reinforce drapery details. At this point Villard apparently considered a drawing complete, for the greatest number of renderings in the manuscript are at this stage. These serve perfectly well as iconographic models if imperfectly as stylistic models. It is interesting to note that many drawings in this state have no detailing of the head or face. It is clear from examining the manuscript hat Villard was content to leave many drawings at this state of completion. What is not clear is why, or when, he elected to bring certain drawings to a more advanced or truly finished state of completion. It is likely that only when Villard decided to \"go public\" with his drawings, adding captions to certain of them and having them bound, did he then select certain figures to bring to completion. One must assume he selected those figures which he considered to be his best renderings in a technical or stylistic sense, for they are generally the most traditional iconographic subjects. Admittedly, it is this finished state which makes these drawings look 'sbetter\" to modern eyes. In any case, once he had made his decision, the subsequent steps in his draperyrendering process are clearly discernible. Fig. 6 also demonstrates the next step, which was to use a thicker, darker ink to define the contour of the figure and to isolate the main volumes within that contour from one another.9 It is important o realize that the tonal contrast between this

Abstract: The appts. is used for monitoring a visual field or for examination of a photograph. The photograph or visual scene is projected onto the screen or target element of a video camera by an optical system and is translated into a series of voltages which may be fed to a computer. The photograph or scene is in effect broken up into a raster of many points. The computer may convert black and white contrast differences into different colours to be shown on the screen of a colour TV set. The results may be recorded as a colour photograph. The system may be used with moving objects, e.g. a traffic scene in which an accident has occurred.

Abstract: PURPOSE:To realize a small size for the input device, by reading and displaying the data out of the memory device in the order of the smaller number of strokes and based on the Japanese rendering. CONSTITUTION:The Chinese character display button 4 is pushed, and the phonetical reading or the Japanese rendering of the Chinese character is supplied through the keyboard unit 1. The control unit reads the data out of the memory device based on the Japanese rendering and then displays the Chinese characters on the display unit 3 with a fixed time interval and in the order of the smaller number of strokes. The operator can have a quick sending by the frame sending buttons 5 and 6, the adverse quick sending by the buttons 7 and 8, or the adverse sending each when necessary.