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The Lyon-Meudon Extragalactic database (LEDA) gives a free access to the main astrophysical parameters for more than 100,000 galaxies. The most common names are compiled allowing users to recover quickly any galaxy. All these measured astrophysical parameters are first reduced to a common system according to well defined reduction formulae leading to mean homogeneized parameters. Further, these parameters are also transformed into corrected parameters from widely accepted models. For instance, raw 21-cm line widths are transformed into mean standard widths after correction for instrumental effect and then into maximum velocity rotation properly corrected for inclination and non-circular velocity. This paper presents the reduction formulae for each parameter: coordinates, morphological type and luminosity class, diameter and axis ratio, apparent magnitude (UBV, IR, HI) and colors, maximum velocity rotation and central velocity dispersion, radial velocity, mean surface brightness, distance modulus and absolute magnitude, and group membership. For each of these parameters intermediate quantities are given: galactic extinction, inclination, K-correction etc.. All these parameters are available from direct connexion to LEDA (telnet lmc.univ-lyon1.fr, login: leda, no passwd OR http://www-obs.univ-lyon1.fr/leda ) and distributed on a standard CD-ROM (PGC-ROM 1996) by the Observatoire de Lyon via the CNRS (mail to petit@obs.univ-lyon1.fr)., Comment: 13 pages, 12 figures. The CDROM of the extragalactic database LEDA is available by mailing to: petit@obs.univ-lyon1.fr

Graphs are useful tools for modeling problems that occur in a variety of fields. In machine vision graph based solutions have been successfully applied to many image processing problems e.g. quad trees for image compression and region adjacency graphs for segmentation. The application of graphs to machine vision problems poses special problems due to the underlying size of the image e.g. a graph representing the base level of a 512x512 image has over 200.000 nodes. The large size of the graphs make issues of both space and time complexity important when designing algorithms for machine vision problems. We present an implementation under LEDA (Library of Efficient Data structures and Algorithms) of DGC (Dual Graph Contraction) for irregular pyramids. In the first section we present the theory behind DGC, in the second an algorithmic specification is derived, and in the third an implementation under LEDA is given followed by a short conclusion.

An automated and highly accurate system for “mapping” 5 cm-diameter beam position monitors (BPMs) used in the Low Energy Demonstrator Accelerator (LEDA) at Los Alamos is described. Two-dimensional data is accumulated from the four micro-stripline electrodes in the probe by sweeping an antenna driven at the LEDA bunching frequency of 350 MHz in discrete steps across the aperture. These data are then used to determine the centroid, first- and third-order sensitivities of the BPM. These probe response coefficients are then embedded in the LEDA control system database to provide normalized beam position information to the operators. A short summary of previous systems we have fielded is given, along with their attributes and deficiencies that had a bearing on this latest design. Lessons learned from this system will, in turn, be used on the next mappers that are currently being designed for 15 cm and 2.5 cm BPMs.

This report documents structural analysis of the Accelerator Production of Tritium Low Energy Demonstration Accelerator (APT/LEDA) Radio Frequency Quadrupole (RFQ) accelerator structure and its associated support frame. This work was conducted for the Department of Energy in support of the APT/LEDA. Structural analysis of the RFQ was performed to quantify stress levels and deflections due to both vacuum loading and gravity loading. This analysis also verified the proposed support scheme geometry and quantified interface loads. This analysis also determined the necessary stiffness and strength requirements of the RFQ support frame verifying the conceptual design geometry and allowing specification of individual frame elements. Complete structural analysis of the frame was completed subsequently. This report details structural analysis of the RFQ assembly with regard to gravity and vacuum loads only. Thermally induced stresses from the Radio Frequency (RF) surface resistance heating were not considered.

Graphlet is a portable, object oriented toolkit for graph editors and graph drawing algorithms, and is the successor of the GraphEd system. Graphlet is based on LEDA and Tcl/Tk. Algorithms can be implemented in C++ and LedaScript, a new scripting language based on Tcl/Tk. The GML format is a portable file format for graphs.

We give an overview of the LEDA platform for combinatorial and geometric computing and an account of its development. We discuss our motivation for building LEDA and to what extent we have reached our goals. We also discuss some recent theoretical developments. This paper contains no new technical material. It is intended as a guide to existing publications about the system. We refer the reader also to our web-pages for more information.

We would like to start this discussion by attempting to make a useful, working distinction between catalogs and databases of astronomical objects. It seems to us that such a distinction could be made based upon the mode of access to the information: A catalog may be considered as a list of objects, almost invariably ordered by coordinates; a database, on the other hand, may be distinguished by its ability to extract a set of objects based on user-given criteria, such as all objects within a certain sky region with magnitudes brighter than m in the blue. Catalogs form the basis of the database, which adds the means of multi-criteria access to the information. In concrete terms, one usually thinks of SIMBAD, NED and LEDA as databases, while an ftp site containing electronic lists of objects may be thought of as a catalog storage warehouse.

This connexion, realized a couple of months ago, is intended first to provide PDAC with proper cross-identifications between LEDA galaxies (which are about 105at present) and the extended objects detected by DENIS (which may be up to 106). Next comes obviously the fruitful exploitation of the scientific resources of both entities.

An attempt is made in this paper to summarise the state of the art in the interaction between the Information Communication Technologies (ICT) that becomes ubiquitous and the electrical power production and distribution. Both are considered to have a difficult task to fulfil enormous rise of demand that is becoming above all expectations. In the same time they technologically interfere in the sense that they mutually help in the fulfilment of their main task while in the same time loading each other with problems inherent to the respective technology. In the paper, we will try to merge our (LEDA laboratory of the University of Niš) own results with ones available in the literature in order to give as complete a picture of the subject as possible.

We report on the design, construction, and test of a new gain monitoring system developed for the 10 000-module lead-glass calorimeter in the WA98 experiment. The system combines precision monitoring and modularity according to the general detector design. It is based on pulsed LEDs and photodiodes. The complete system was successfully used in an electron calibration and during the first Pb-ion beam time at the CERN SPS.

A program checker verifies that a particular program execution is correct. We give simple and efficient program checkers for some basic geometric tasks. We report about our experiences with program checking in the context of the LEDA system. We discuss program checking for data structures that have to rely on user-provided functions.

In 1981 our scientific team was involved in the management of large amount of HI-data. The goal, at this time, was only our own scientific research. In a collaboration with G. and A. de Vaucouleurs we started to add optical information to our first HI-catalog. It was our first contact with the difficult problem of cross-identifying two catalogs and merging them. To face this problem, one of us (GP) decided to rationalize the management by creating a database. It was created in 1983 at Lyon Observatory. LEDA is thus the oldest Extragalactic Database. Since this time, the database has been continuously updated and improved.

Having discussed the Western Design, it is time to return to the course of relations in Europe and consider the crisis that threatened Cromwell’s rapprochement with France when his attack on Spanish territory was already under way. Despite Spain’s public fury at Cromwell’s ‘unexpected treachery’, their government was clearly aware of the Design’s target since the summer of 1654, although the actual course of the attack was not known until August 1655. Throughout this period Cardenas continued to negotiate and in May 1655 Spain sent the Marquis of Leda to assist him. It was apparent that Cromwell was unlikely to mitigate his harsh demands, the King’s ‘two eyes’, and as Leda did not offer any new terms his mission was not intended to prevent a breach by surrendering to Cromwell’s demands. However, France feared for his success despite current events in America. Spain did not retaliate until it was known that Cromwell’s expedition had been rebuffed and that his military power was not as great as was feared in 1654.

We report the discovery of an interesting and rare, rectangular-shaped galaxy. At a distance of 21 Mpc, the dwarf galaxy LEDA 074886 has an absolute R-band magnitude of -17.3 mag. Adding to this galaxy's intrigue is the presence of an embedded, edge-on stellar disk (of extent 2R_{e,disk} = 12 arcsec = 1.2 kpc) for which Forbes et al. reported V_rot/sigma ~ 1.4. We speculate that this galaxy may be the remnant of two (nearly edge-one) merged disk galaxies in which the initial gas was driven inward and subsequently formed the inner disk, while the stars at larger radii effectively experienced a dissipationless merger event resulting in this `emerald cut galaxy' having very boxy isophotes with a_4/a = -0.05 to -0.08 from 3 to 5 kpc. This galaxy suggests that knowledge from simulations of both `wet' and `dry' galaxy mergers may need to be combined to properly understand the various paths that galaxy evolution can take, with a particular relevance to blue elliptical galaxies., Comment: To appear in ApJ. Six pages including references and figures

(1998). Author’s Reply: Relative Importance of Risk Sources in Insurance Systems - Discussion by Emilia Di Lorenzo; Griselda Deelstra; Leda Minkova; Nikolai Kolev. North American Actuarial Journal: Vol. 2, No. 2, pp. 51-52.

Tooby, John, and Leda Cosmides. Does Beauty Build Adapted Minds? Toward an Evolutionary Theory of Aesthetics, Fiction, and the Arts. Puzzlingly, humans in all cultures engage in a broad variety of aesthetically oriented activities that appear to have no obvious evolutionary utility, including immersion in those falsehoods called fiction. We argue that, despite appearances, aesthetically oriented activities are evolutionarily functional, and are the product of evolved adaptations designed to cause such experiences. These are adaptations whose function is to (1) assist in constructing the adaptations that constitute our species-typical neurocognitive design, and (2) bring those adaptations into a state of effective readiness, individually tailored to deal with the specific adaptive demands that they will confront during that person's life.

A few months back, when the night sky was darker than Leda had ever seen, she stepped through the worn doorframe of the Q Lounge. The suddenness of thick, smoky air left her slightly faint. After that, it was easy enough, Leda saw him across the damp, just-wiped bar she did nothing but hold the glance a second too long. Sure enough, as if she had called out his name, he walked over a slight smile and straw hat.

Aldous Huxley sent his brother a copy of "Leda" in response to Julian's letter announcing his engagement to Juliette Baillot. Technically the story of an adultery, it made an odd engagement present. As a poem about recurring disillusionment, however, it can be construed as indirect advice to an elder brother and a prospective sister-in-law not to expect too much. The newly engaged pair missed the poem's central point completely. Julian later surmised that their "euphoric state" caused this obtuseness, "for when Juliette wrote a note of glowing praise to Aldous, he replied [on 22 January 1919] with the following snub"

“oysons bridez … et aultres telles painctures contrefaictes à plaisir pour exciter le monde à rire.” (Gargantua, Prologue)It is no novelty to stress the paradistic aspects of Rabelais's style. As early as 1915, Emile Besch had described Gargantua and Pantagruel as “une parodie des romans de chevalerie,” and this broad critical assessment has not really been seriously challenged ever since. Yet most of the studies devoted to Rabelais's comical imitations seem to concentrate either on what he owes to the ancient, medieval or humanistic tradition, or on the specific techniques through which he mocks or distorts various genres, modes or styles. More specifically, very little attention has been paid so far to Rabelais's attitude vis-à-vis art works of his time, although we know very well that, like many other contemporary writers, he had a keen interest in pictorial compositions.

The LEDA system, developed for the codification of field data and information, is user, machine, and geology oriented. It is used to codify stratigraphic and morphologic data required in mapping Quaternary deposits. Flexibility in the system is achieved by the selection of distinct types of data as units of data collection, which are reported on six type-cards extending the length of an 80-column punchcard. These type-cards are (1) Location, (2) Stratigraphic Unit, (3) Composition, (4) Orientation (5) Commentary, and (6) Stratigraphic Measurement. The type-cards are reproduced on pocket-size field data sheets in the following order; (1) one card for the location and one card for the description of a unit; (2) two cards for the description of units; (3) three cards for composition or orientation data; (4) four cards for commentary; and (5) two cards for stratigraphic measurements. There is an additional field sheet provided for diagrams and polaroid photos, the information of which is not codifiable. In the field, the sheets are placed in a loose-leaf binder with a flipout chart containing the code. The link between the type-cards making up a station file is provided by the field station code which occurs on each card in the data file but is reported only once on each field sheet. The filling out of the location card is obligatory for any particular station, whereas the other cards may be used in any order or number according to the type and length of information sought.

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The comparison of consolidated undrained triaxial results on sensitive Leda clay sampled by six different sampling methods is presented. The results indicate that the failure index, represented by the axial stress difference as a fraction of the axial failure stress difference against strain plots, are widely different at very low consolidation pressures, but are similar and approximate to the results from block samples as the consolidation pressure is increased. The pore pressure coefficient A appears to be independent of the sampling method and remains remarkably consistent throughout any test (up to failure) except where the confining pressure is very low or above the preconsolidation pressure.Routine commercial sampling methods (including laboratory preparation) using 50-mm diameter samples were found to partially destroy the cementation bonds, causing a decrease in strength at low confining pressures and an unsafe increase in strength at medium confining pressures. This trend is decreased by better sampling.

The preliminary design of an electron storage ring dedicated to the free electron laser operation, is presented. The main feature of the proposed laser is the complete tunability in the wavelength range 0.3 ?m < ? < 20 ?m with an output average power of the order of 1 kW and an efficiency, electron beam-laser beam, of ~ 2%.