4,769 research outputs found
Off-line computing for experimental high-energy physics
The needs of experimental high-energy physics for large-scale computing and data handling are explained in terms of the complexity of individual collisions and the need for high statistics to study quantum mechanical processes. The prevalence of university-dominated collaborations adds a requirement for high-performance wide-area networks. The data handling and computational needs of the different types of large experiment, now running or under construction, are evaluated. Software for experimental high-energy physics is reviewed briefly with particular attention to the success of packages written within the discipline. It is argued that workstations and graphics are important in ensuring that analysis codes are correct, and the worldwide networks which support the involvement of remote physicists are described. Computing and data handling are reviewed showing how workstations and RISC processors are rising in importance but have not supplanted traditional mainframe processing. Examples of computing systems constructed within high-energy physics are examined and evaluated
Resources and Results in Union Rivalry: A Case Study
L'Association des employés de soutien de l'Université Laurentienne (AESUL) s'est méritée le titre de premier syndicat indépendant d'un groupe d'employés de soutien à être accréditée sous la Loi des relations du travail dans une université d'Ontario, et ce après un conflit de rivalité syndicale fort coloré avec le Syndicat canadien de la fonction publique (SCFP). Certains estiment que l'organisation est un processus par lequel on s'efforce d'abord de vendre l'idée du syndicalisme pour ensuite vanter les avantages d'un syndicat en particulier. Quand il s'agit d'une bataille entre syndicats concurrents, il est loisible d'examiner les moyens utilisés par chacun d'eux pour prôner leurs avantages respectifs.La présente analyse rétrospective et approfondie permet de mettre en relief trois points qui ont concouru à l'obtention du résultat final: le rôle des facteurs non économiques reliés au travail, l'idée que l'on se fait du syndicalisme et les moyens d'influer sur les décisions à prendre.Les données de cette étude ont été tirées des dossiers des deux syndicats en présence, de ceux de la Commission des relations du travail de l'Ontario ainsi que de ceux de l'Université Laurentienne. Le représentant régional du SCFP, des membres du comité de direction de l'AESUL, de l'ancien recteur de l'Université ainsi que du directeur des services à l'époque ont été longuement interviewés.L'AESUL doit son existence à l'Association des employés de bureau de l'Université qui, à ses débuts en 1970, n'était pas accréditée et qui comptait dans ses rangs des employés du bureau, des dactylos, des expéditeurs et des receveurs, les techniciens en bibliotechnie, les employés des presses universitaires et les perforatrices. À ce moment, le SCFP commençait à faire du recrutement dans le secteur des employés de bureau et, pendant les premiers mois de 1973, il s'est efforcé d'obtenir l'adhésion de ce groupe d'employés à l'Université Laurentienne. Les effectifs y étaient assez nombreux pour retenir l'attention d'un syndicat aussi important. Le comité exécutif de l'AESUL a jugé que la tentative du SCFP était en quelque sorte une effraction.La tension était considérable. Les partisans des deux camps s'affairaient à poser des affiches, à arracher celles de la partie adverse peu de temps avant l'heure de la fermeture des bureaux afin de s'assurer que les employés en prendraient connaissance avant l'heure de la sortie du travail. L'administration de l'Université fermait les yeux sur cette activité. Les partisans de l'AESUL faisaient valoir les avantages suivants: pouvoir accru de négociation, statut juridique reconnu, autonomie de l'association et protection contre l'intervention d'un tiers en cours de convention collective. De son côté, le SCFC insistait sur le pouvoir de négociation.En juillet 1973, quand l'AESUL a demandé l'accréditation, le SCFP s'y est opposé en accusant l'Université de favoriser l'association. Un mois plus tard, après une deuxième audition devant la Commission ontarienne, cette dernière décréta un vote qui donna lieu à une nouvelle campagne de propagande. Le vote fut tenu en octobre.Il est bon de signaler que, en aucun temps, l'AESUL n'a parlé ouvertement de syndicat. Il était question d'accréditation, mais non de syndicat. Même s'il existait beaucoup de relations entre les employés de l'Université et ceux del’INCO et de laFalconbridge qui sont syndiqués, le personnel de bureau de l'Université ne trouvait pas convenable de former un syndicat. L'idée de syndicat détonnait dans un milieu universitaire. La communauté de Sudbury avait toujours considéré l'Université comme une institution de haut savoir. Le concept syndicat ne pouvait s'appliquer ni à l'endroit ni au milieu de travail. C'est pourquoi les responsables de la campagne de recrutement se sont gardés d'utiliser le terme « syndicat », et ceci en dépit du fait que le syndicalisme est une institution bien connue à Sudbury.Il faut se demander pourquoi le SCFP, qui possédait ressources et compétence, a perdu cette bataille. C'est que l'AESUL a su miser sur les problèmes du travail. Eneffet, sur les vingt-trois points que cette dernière a touchés, dix-huit portaient sur les problèmes inhérents au travail et cinq seulement se rapportaient aux salaires et aux avantages sociaux. Au contraire, le SCFP a mis presque exclusivement l'accent sur ces deux points.Ce qui ressort de cette étude, c'est que l'AESUL doit son succès en grande partie à sa situation de premier occupant et à la facilité de persuader des gens qu'elle connaissait bien. Les dirigeants étaient au courant des problèmes de chaque petit groupe d'employés. Ces facteurs se sont avérés plus efficaces que les arguments de propagande directe, même si les derniers jours de la campagne furent marqués d'une chaude lutte. Quant à l'Université, elle s'est montrée très discrète tout au long du débat. En résumé, ce sont des motifs d'ordre pratique qui ont poussé les employés à favoriser l'Association plutôt que le syndicat.This paper shows the asymetric disequilibrium between available resources and results in the course of a union recruiting campaign in a case study of an experience of CUPE and LUSSA at Laurentian University
Spacecraft instrument calibration and stability
The following topics are covered: instrument degradation; the Solar Backscatter Ultraviolet (SBUV) Experiment; the Total Ozone Mapping Spectrometer (TOMS); the Stratospheric Aerosol and Gas Experiment 1 (SAGE-1) and SAGE-2 instruments; the Solar Mesosphere Explorer (SME) UV ozone and near infrared airglow instruments; and the Limb Infrared Monitor of the Stratosphere (LIMS)
An extreme ultraviolet spectrometer experiment for the Shuttle Get Away Special Program
An extreme ultraviolet (EUV) spectrometer experiment operated successfully during the STS-7 mission in an experiment to measure the global and diurnal variation of the EUV airglow. The spectrometer is an F 3.5 Wadsworth mount with mechanical collimator, a 75 x 75 mm grating, and a bare microchannel plate detector providing a spectral resolution of 7 X FWHM. Read-out of the signal is through discrete channels or resistive anode techniques. The experiment includes a microcomputer, 20 Mbit tape recorder, and a 28V, 40 Ahr silver-zinc battery. It is the first GAS payload to use an opening door. The spectrometer's 0.1 x 4.2 deg field of view is pointed vertically out of the shuttle bay. During the STS-7 flight data were acquired continuously for a period of 5 hours and 37 minutes, providing spectra of the 570 A to 850 A wavelength region of the airglow. Five diurnal cycles of the 584 A emission of neutral helium and the 834 A emission of ionized atomic oxygen were recorded. The experiment also recorded ion events and pressure pulses associated with thruster firings. The experiment is to fly again on Mission 41-F
Searching edges in the overlap of two plane graphs
Consider a pair of plane straight-line graphs, whose edges are colored red
and blue, respectively, and let n be the total complexity of both graphs. We
present a O(n log n)-time O(n)-space technique to preprocess such pair of
graphs, that enables efficient searches among the red-blue intersections along
edges of one of the graphs. Our technique has a number of applications to
geometric problems. This includes: (1) a solution to the batched red-blue
search problem [Dehne et al. 2006] in O(n log n) queries to the oracle; (2) an
algorithm to compute the maximum vertical distance between a pair of 3D
polyhedral terrains one of which is convex in O(n log n) time, where n is the
total complexity of both terrains; (3) an algorithm to construct the Hausdorff
Voronoi diagram of a family of point clusters in the plane in O((n+m) log^3 n)
time and O(n+m) space, where n is the total number of points in all clusters
and m is the number of crossings between all clusters; (4) an algorithm to
construct the farthest-color Voronoi diagram of the corners of n axis-aligned
rectangles in O(n log^2 n) time; (5) an algorithm to solve the stabbing circle
problem for n parallel line segments in the plane in optimal O(n log n) time.
All these results are new or improve on the best known algorithms.Comment: 22 pages, 6 figure
Hydrologic Response and Watershed Sensitivity to Climate Warming in California's Sierra Nevada
This study focuses on the differential hydrologic response of individual watersheds to climate warming within the Sierra Nevada mountain region of California. We describe climate warming models for 15 west-slope Sierra Nevada watersheds in California under unimpaired conditions using WEAP21, a weekly one-dimensional rainfall-runoff model. Incremental climate warming alternatives increase air temperature uniformly by 2°, 4°, and 6°C, but leave other climatic variables unchanged from observed values. Results are analyzed for changes in mean annual flow, peak runoff timing, and duration of low flow conditions to highlight which watersheds are most resilient to climate warming within a region, and how individual watersheds may be affected by changes to runoff quantity and timing. Results are compared with current water resources development and ecosystem services in each watershed to gain insight into how regional climate warming may affect water supply, hydropower generation, and montane ecosystems. Overall, watersheds in the northern Sierra Nevada are most vulnerable to decreased mean annual flow, southern-central watersheds are most susceptible to runoff timing changes, and the central portion of the range is most affected by longer periods with low flow conditions. Modeling results suggest the American and Mokelumne Rivers are most vulnerable to all three metrics, and the Kern River is the most resilient, in part from the high elevations of the watershed. Our research seeks to bridge information gaps between climate change modeling and regional management planning, helping to incorporate climate change into the development of regional adaptation strategies for Sierra Nevada watersheds
Approximating the Maximum Overlap of Polygons under Translation
Let and be two simple polygons in the plane of total complexity ,
each of which can be decomposed into at most convex parts. We present an
-approximation algorithm, for finding the translation of ,
which maximizes its area of overlap with . Our algorithm runs in
time, where is a constant that depends only on and .
This suggest that for polygons that are "close" to being convex, the problem
can be solved (approximately), in near linear time
Folian-cv1 Is a Member of a Highly Acidic Phosphoprotein Class Derived From the Foliated Layer of the Eastern Oyster (\u3ci\u3eCrassostrea virginica\u3c/i\u3e) Shell and Identified in Hemocytes and Mantle
The proteins derived from the foliated shell layer of the oyster, Crassostrea virginica, are unusually acidic and highly phosphorylated. Here we report the identification of a gene encoding a member of this class of phosphoproteins that we collectively refer to as folian. Using an in silico approach, a virtual probe was constructed from an N-terminal sequence (DEADAGD) determined for a 48 kDa folian phosphoprotein and used to screen an oyster EST databank. A sequence that matched the N-terminus of the 48 kDa protein was found and used to identify the full-length gene from a C. virginica BAC library. The molecular weight of the deduced gene product is 32 kDa and was named folian-cv1. Genomic Southern analysis revealed two variants of the gene. The mature protein is composed of 43.3% Asp, 32.6% Ser, and 9.1% Glu with 37.5% of the amino acids of the protein potentially phosphorylated. The primary sequence of folian-cv1 is organized in blocks, with a short relatively hydrophobic block at the N-terminus and with the remainder containing low complexity regions largely dominated by aspartic acid and serine. Overall, the protein is predicted to be highly disordered. PCR and sequence analyses identified folian-cv1 expression in the mantle and hemocytes. Immuno-histochemical staining of mantle tissue reveals that cells of the shell-facing epithelium and in the periostracal groove secrete a continuous layer of folian-positive material and that folian-positive hemocytes move through the mantle epithelium. The function in shell formation of folian proteins including folian-cv1 is not known. However, based on the complexity of this class of proteins and the two methods of their delivery to the region of shell formation, it is possible they are involved in diverse ways in this process
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