The introduction of space technology power systems into developing countries

Between 1978 and 1984, NASA-Lewis was responsible for the design, fabrication, installation and operational support of 57 photovoltaic power systems in 27 countries. These systems were installed in locations not served by a central power system and ranged in size from 40 W for powering street lights to 29 kW for providing power to a complete village. Several of the system projects had socio/economic studies components that provided for an assessment of how the introduction of both electricity and a novel high technology power system affected the users and their society

“comets importing change of Times and States”: ephemerae and process among the Tabwa of Zaire

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136677/1/ae.1982.9.4.02a00060.pd

African Religious Groups and Beliefs: Papers in Honor of William R. Bascom. SIMON OTTENBERG, ed

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136516/1/ae.1984.11.3.02a00240.pd

The Control of pH and Total Alkalinity or Total Carbonate in Aquatic Bioassays

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142267/1/tafs0752.pd

L'aura d'Amadou Bamba. Photographie et fabulation dans le Sénégal urbain

RÉSUMÉL'aura d'Amadou Bamba. Photographie et fabulation dans le Sénégal urbainDepuis 1988, le Sénégal urbain a vu proliférer les arts populaires. Un sujet se détache en nombre et en importance : Amadou Bamba (1853-1927), saint soufi du Sénégal autour de qui a été créée la Voie mouride. Toutes les images de Bamba renvoient à une seule photographie prise vers 1913, photographie dont les particularités offrent une suite sans fin d'occasions de reconnaître des significations cachées et des messages, à partir de l'épisté-mologie soufie. Les auteurs présentent une ethnographie du Sénégal et un exposé des théories de la représentation, depuis la notion de surréalisme implicite à la photographie de Susan Sontag, jusqu'au sens de la catachrèse génératrice de nouvelles règles et significations de Jacques Derrida, qui permettent de remettre en question et d'élargir la notion proposée par Walter Benjamin de « l'aura » des œuvres d'art, pour y inclure une compréhension de l'impact des images de Bamba. La prolifération récente des fresques représentant Bamba contribue à la déconstruction de la « mémoire monolithique » du régime colonial et immédiatement postcolonial et à la fabulation d'un collage mnémonique tout à fait nouveau.Mots clés : Roberts, Nooter Roberts, représentation, photographie, aura, mouridisme, islam, SénégalABSTRACTThe Aura ot Amadou Bamba : Photography and Fabulation in Urban SénégalSince 1988, urban Senegal has seen a flowering of popular arts, with one subject standing out in number and prominence : Amadou Bamba (1853-1927), a Senegalese Sufi saint around whom the Mouride Way has been created. Ail images of Bamba are based upon a single photograph taken in about 1913, the particularities of which provide endless opportunities for recognition of hidden meanings and messages through Sufi epistemology. The authors' Senegalese ethnography and a discussion of theories of representation ranging from Susan Sontag's notion of the surrealism implicit to photography to Jacques Derrida's sense of catachresis as producing new rules and meanings, allow Walter Benjamin's notion of thé "aura" of art works to be challenged and extended to provide an understanding of the impact of images of Bamba. Recent proliferation of wall paintings depicting Bamba contributes to deconstruction of the "monolithic memory" of colonial and early-postcolonial régimes and thé fabulation of an altogether new mnemonic collage.Key words : Roberts, Nooter Roberts, représentation, photography, aura, Mouridism, Islam, Sénéga

The Probable Detection of SN 1923A: The Oldest Radio Supernova?

Based upon the results of VLA observations, we report the detection of two unresolved radio sources that are coincident with the reported optical position of SN 1923A in M83. For the source closest to the SN position, the flux density was determined to be 0.30 +/- 0.05 mJy at 20 cm and 0.093 +/- 0.028 mJy at 6 cm. The flux density of the second nearby source was determined to be 0.29 +/- 0.05 at 20 cm and 0.13 +/- 0.028 at 6 cm. Both sources are non-thermal with spectral indices of alpha = -1.0 +/- 0.30 and -0.69 +/- 0.24, respectively. SN 1923A has been designated as a Type II-P. No Type II-P (other than SN 1987A) has been detected previously in the radio. The radio emission from both sources appears to be fading with time. At an age of approximately 68 years when we observed it, this would be the oldest radio supernova (of known age) yet detected

Frictional cooling of positively charged particles

One of the focuses of research and development towards the construction of a muon collider is muon beam preparation. Simulation of frictional cooling shows that it can achieve the desired emittance reduction to produce high-luminosity muon beams. We show that for positively charged particles, charge exchange interactions necessitate significant changes to schemes previously developed for negatively charged particles. We also demonstrate that foil-based schemes are not viable for positive particles.Comment: 15 pages, 6 figure

Completely Explosive Autonomous High-Voltage Pulsed-Power System Based on Shockwave Ferromagnetic Primary Power Source and Spiral Vector Inversion Generator

Novel explosive and conventional pulsed-power technologies were combined, and a series of explosive-driven high-voltage power supplies was designed, built, and tested. The power supply contained an explosive-driven high-voltage primary power source based on the fundamental physical effect of shockwave demagnetization of Nd2 Fe14B high-energy ferromagnet and a power-conditioning stage. The volume of the energy-carrying ferromagnetic elements in the shockwave ferromagnetic generators (FMGs) was 8.75 cm3. The power-conditioning stage was based on the spiral vector inversion generator (VIG). The combined FMG-VIG system demonstrated successful operation and good performance. The output-voltage pulse amplitude of the combined FMG-VIG system exceeded 40 kV, with a rise time of 6.2 ns. The methodology was developed for digital simulation of the operation of completely explosive FMG-VIG system. Experimental results obtained are in a good agreement with the results of digital calculations performed

The analytic structure of heavy quark propagators

The renormalised quark Dyson-Schwinger equation is studied in the limit of the renormalised current heavy quark mass m_R --> infinity. We are particularly interested in the analytic pole structure of the heavy quark propagator in the complex momentum plane. Approximations in which the quark-gluon vertex is modelled by either the bare vertex or the Ball-Chiu Ansatz, and the Landau gauge gluon propagator takes either a gaussian form or a gaussian form with an ultraviolet asymptotic tail are used.Comment: 21 pages Latex and 5 postscript figures. The original version of this paper has been considerably extended to include a formalism dealing with the renormalised heavy quark Dyson-Schwinger equation and uses a more realistic Ansatz for the gluon propagator