827 research outputs found

    The upgrading of fire safety in historic buildings

    Get PDF
    There is a seemingly continual erosion of our cultural heritage due to fires in historic buildings. Some of these fires result in partial loss of the asset, some result in total loss – in all cases irreplaceable historic fabric is destroyed. Accurate recording for fires in historic buildings is problematic, but such data as has been collated indicates that the level of loss is high. One of the key factors in achieving robust fire safety in historic buildings is the upgrading of physical fire protection measures. It has been suggested that we should assume a fire event is probable, and together with a context in which outside help might be some time in arriving, such measures are considered crucial in containing the fire and raising the alarm as quickly as possible. This article considers passive and active fire protection measures, using case study material to provide illustrative examples. Where it might be expected that conservation requirements, aiming to avoid negative impact to character and significance, might hinder disruptive physical interventions to improve fire protection, in fact a great deal can be achieved. Such a pragmatic approach is arguably necessary for the safety and preservation of built heritage, when the alternative might otherwise be yet another burnt-out shell

    Critical Dimensions in Architectural Photography: Contributions to Architectural Knowledge

    Get PDF
    This paper illustrates and explores three critical dimensions of photography in architecture, each of which informs the production of images, texts, and other artifacts which establish what might be called a building’s media footprint. The paper’s broad goal is to question the extent to which these critical dimensions are relevant to architectural decision-making processes. Acknowledging that such dimensions as the ones examined here rarely predict an architect’s specific design decisions in a transparent manner, the paper discusses not only the decisions made by architects during the process of designing buildings, but the decisions made by critics, visitors, and members of the general public as they engage in activities such as visiting buildings, writing about them and, particularly, photographing them. First, the text discusses the potential of buildings to operate as mechanisms for producing images, in the sense originated by Beatriz Colomina. The question is developed through the analysis of the space of photography – mapping of points of view, directions of view, and fields of view of defined photographic collections. Secondly, it considers photography’s complicity in the canonization of buildings, and specifically, the extent to which photography is responsible for distinguishing between major and minor architectural works. Finally, the essay examines the erosion over time of photography’s historical power to frame when confronted with contemporary technologies of virtual reality and photo realistically rendered digital models. Each of these critical dimensions, or concepts, develops a specific aspect of how photographic information about buildings is organized, structured, and disseminated, and is thus only part of the larger project of architectural epistemology, which inquires into this wider field. This will be done through an examination of the Mies van der Rohe-designed Commons Building at ITT in Chicago and the evolution of its relationship with architectural photography and photographic representation – both on its own terms and through the prism of the Rem Koolhaas-designed McCormick Tribune Student Center, which adds to and incorporates the Commons Building. Until the end of the twentieth century, the Commons Building on the campus of the Illinois Institute of Technology was generally considered one of Mies van der Rohe’s lesser works. Reportedly neglected by its own architect during the design process, and frequently marginalized in academic discussions of the campus, when mentioned at all the building was often cited as an unrefined prototype of Crown Hall. This discourse took a new direction when in 1998, Rem Koolhaas/OMA won a design competition for a student center on the IIT campus: uniquely among the competition entries, Koolhaas’s design incorporated the Commons Building within a new context – what ultimately became the McCormick Tribune Campus Center (MTCC). When critics concluded that the incorporation of the Commons Building into the larger whole could compromise its integrity as an exemplar of Mies’s work, the building became the object of renewed interest and controversy. The two projects considered here show a clear evolution in architecture’s relationship with the photographic image. Specifically, the history of the Commons Building can be traced through photographs: during and shortly following its construction, the building was photographed as part of Mies’s own attention to publicity; it was documented as part of historical analyses; and over time it was visited and photographed by casual and amateur photographers. Following the competition results, photographs of the Commons Building were strategically deployed by both proponents and critics of Koolhaas’s design. Contemporary photographs of the building appear in architectural and campus guidebooks and on websites such as Flickr.com. Examining the ways in which photographs of the Commons Building appear in these various contexts allows discussion of the critical dimensions identified above and permits us to trace the evolution of the mutually reinforcing relationship between architecture and photography

    Search for antihelium in cosmic rays

    Get PDF
    The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle Discovery during flight STS-91 in a 51.7 degree orbit at altitudes between 320 and 390 km. A total of 2.86 * 10^6 helium nuclei were observed in the rigidity range 1 to 140 GV. No antihelium nuclei were detected at any rigidity. An upper limit on the flux ratio of antihelium to helium of < 1.1 * 10^-6 is obtained.Comment: 18 pages, Latex, 9 .eps figure

    A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01

    Get PDF
    The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics experiment that will study cosmic rays in the 100MeV\sim 100 \mathrm{MeV} to 1TeV1 \mathrm{TeV} range and will be installed on the International Space Station (ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected 10810^8 cosmic ray triggers. Part of the \emph{Mir} space station was within the AMS-01 field of view during the four day \emph{Mir} docking phase of this flight. We have reconstructed an image of this part of the \emph{Mir} space station using secondary π\pi^- and μ\mu^- emissions from primary cosmic rays interacting with \emph{Mir}. This is the first time this reconstruction was performed in AMS-01, and it is important for understanding potential backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor stylistic and grammer change

    Protons in near earth orbit

    Get PDF
    The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is parameterized by a power law. Below the geomagnetic cutoff a substantial second spectrum was observed concentrated at equatorial latitudes with a flux ~ 70 m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated trajectory and originate from a restricted geographic region.Comment: 19 pages, Latex, 7 .eps figure

    A blot on the landscape? Civic memory and municipal public parks in early twentieth century Manchester

    Get PDF
    This paper examines the decision to locate the façade of Manchester’s old Town Hall in a public park (Heaton Park) in 1912. It argues that, in so doing, the city’s Parks and Cemeteries committee was attempting to refine the didactic space of the park as a site of civic memory. The early Victorian urban parks had sought to educate their visitors through their museums, art galleries and exhibition spaces, glasshouses and carefully-planned and planted walkways. The insertion into this environment of part of a former civic building was intended to remind the visitors of their civic history and to warn surrounding districts of the expansionist tendencies of the city of Manchester. The failure to identify the façade or to connect it to its surroundings meant that its meaning was ultimately lost to many parks visitors and it remained in place as a civic folly. Public parks presented the municipal authorities with an opportunity to highlight the provision of recreation and leisure facilities, but also an occasion to re-invent the municipal tradition. However, as this paper shows, such gestures were often futile in the complex and contested space of the public park

    Isotopic Composition of Light Nuclei in Cosmic Rays: Results from AMS-01

    Get PDF
    The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arrival in the heliosphere. In this paper we present measurements of the isotopic ratios 2H/4He, 3He/4He, 6Li/7Li, 7Be/(9Be+10Be) and 10B/11B in the range 0.2-1.4 GeV of kinetic energy per nucleon. The measurements are based on the data collected by the Alpha Magnetic Spectrometer, AMS-01, during the STS-91 flight in 1998 June.Comment: To appear in ApJ. 12 pages, 11 figures, 6 table

    Ponte et stratégie de la reproduction chez les femelles du tacaud Trisopterus luscus (Gadidés) du plateau continental de la Galice, nord-ouest de l'Espagne

    Get PDF
    [EN] Pouting, Trisopterus luscus is harvested commercially on the Galician shelf by the Spanish inshore artisanal fleet. In spite of a substantial decrease in pouting catches, fishery regulations are limited to size length restrictions. This study provides biological data including length-at-maturity based on histological methods, seasonal maturation, spawning and fecundity. A collection 443 females, from 17 to 42 cm in total length, were sampled from landings (December 2003 to December 2004). Pouting length-at-maturity was estimated as 19.2 cm on average. Pouting females in spawning condition were observed throughout the year and the number of developing oocytes ranged from 20 000 to 1 327 000. Peak spawning was observed between February and April, which correlated well with trends in gonadosomatic index, and inverse to condition factor and hepatosomatic index. Histological examination of the gonads revealed that pouting ovarian development organization is asynchronous, and fecundity is probably determinate.[FR] Le tacaud, Trisopterus luscus est pêché par la flotte artisanale espagnole. En dépit d'une diminution substantielle des captures de tacaud, la pêche est réglementée uniquement à partir d'une taille minimum commerciale. Cette étude fournit des données biologiques comprenant la taille à maturité sexuelle basée sur l'histologie, la maturation saisonnière, la ponte et la fécondité. Un échantillon de 443 femelles, de 17 à 42 cm longueur totale, est examiné à partir des débarquements durant une année (de décembre 2003 à décembre 2004). La taille moyenne à maturité sexuelle est estimée à 19,2 cm. Les femelles de tacaud en condition de ponte sont observée tout au long de l'année et le nombre d'ovocytes s'étend de 20 000 to 1 327 000 par individu. Les pics de ponte sont observés entre février et avril, ce qui est bien corrélé avec l'évolution du rapport gonado-somatique et inverse de celle du facteur de condition et du rapport hépato-somatique. L'étude histologique révèle que le développement ovarien chez le tacaud est asynchrone, et que la fécondité est probablement déterminée.Peer reviewe

    Relative Composition and Energy Spectra of Light Nuclei in Cosmic Rays: Results from AMS-01

    Get PDF
    Measurement of the chemical and isotopic composition of cosmic rays is essential for the precise understanding of their propagation in the galaxy. While the model parameters are mainly determined using the B/C ratio, the study of extended sets of ratios can provide stronger constraints on the propagation models. In this paper, the relative abundances of light-nuclei lithium, beryllium, boron, and carbon are presented. The secondary-to-primary ratios Li/C, Be/C, and B/C have been measured in the kinetic energy range 0.35-45 GeV nucleon[superscript –1]. The isotopic ratio [superscript 7]Li/[superscript 6]Li is also determined in the magnetic rigidity interval 2.5-6.3 GV. The secondary-to-secondary ratios Li/Be, Li/B, and Be/B are also reported. These measurements are based on the data collected by the Alpha Magnetic Spectrometer AMS-01 during the STS-91 space shuttle flight in 1998 June. Our experimental results are in substantial agreement with other measurements, where they exist. We describe our light-nuclei data with a diffusive-reacceleration model. A 10%-15% overproduction of Be is found in the model predictions and can be attributed to uncertainties in the production cross-section data
    corecore