Neutrinos from galactic sources of cosmic rays with known gamma-ray spectra

We describe a simple procedure to estimate the high-energy neutrino flux from the observed gamma-ray spectra of galactic cosmic ray sources that are transparent to their gamma radiation. We evaluate in this way the neutrino flux from the supernova remnant RX J1713.7-3946, whose very high-energy gamma-ray spectrum (assumed to be of hadronic origin) is not a power law distribution according to H.E.S.S. observations. The corresponding muon signal in neutrino telescopes is found to be about 5 events per square kilometer per year in an ideal detector.Comment: 6 pages, 1 figure; accepted in Astroparticle Physic

A study of methods of prediction and measurement of the transmission of sound through the walls of light aircraft

The acoustic intensity technique was applied to the sound transmission loss of panel structures (single, composite, and stiffened). A theoretical model of sound transmission through a cylindrical shell is presented

The Purdue University Get Away Special II (PUGAS II)

The Purdue University Get Away Special Project (PUGAS) is a student-run organization dedicated to preparing payloads for flight on NASA's space shuttle. The first such payload (PUGAS I) flew on Challenger in 1983. The second payload (PUGAS II) should be ready by the end of 1988 and will include three experiments. The first experiment will involve the production of tin metal foam under microgravity conditions. The second experiment will focus on the desorption of water from carbon-epoxy composite materials. The third experiment will use a solid polymeric material to detect radiation in space

Irritable bowel syndrome : Reply

In reply to a letter to the Editor, original article Crocker K, Chur-Hansen A, Andrews J. Interpersonal relationships for patients with irritable bowel syndrome: A qualitative study of gps' perceptions Australian Family Physician 42(11):805-810 2013Katie Crocker, Anna Chur-Hansen, Jane Andrew

Modeling of Selective Area Laser Deposition Vapor Infiltration (SALDVI) of Silicon Carbide

Selective Area Laser Deposition Vapor Infiltration (SALDVI) is a developing solid freeform fabrication (SFF) technique in which porous layers of powder are densified by infiltrating the pore spaces with solid material deposited from a gas precursor during laser heating. A 3D finite element model was developed that simulates SALDVI of silicon carbide. The model predicts the laser input power and the distribution of vapor deposited SiC within the powder bed as well as on the surface of the powder bed (SALD). The model considers a moving Gaussian distribution laser beam, temperatureand porous-dependent thermal conductivity, specific heat and temperature-dependent deposition rate. Furthermore, the model also includes closed-loop control of the laser power to achieve a desired target processing temperature on the top surface of the power bed. The simulation results agree fairly well with experimental data for simple geometries and offer guidelines for further experimental studies of the SALDVI process.Mechanical Engineerin

The economic organization of nuclear plant projects : some cross-national comparisons

This paper examines the relationship between the economic organization of the nuclear power industry and its perfornmance in designing and building nuclear power plants. The institutional relationships that link French, West German and Japanese utilities with their nuclear plant suppliers are described and compared. The focus is on three interrelated aspects of these relationships: (1) the extent of utility involvement in the supply process; (2) the extent to which the various supply functions are "horizontally" integrated; and (3) the nature of the contracts linking the utilities and their suppliers. The transaction cost approach provides the framework for the analysis. The central idea underlying this approach is that important efficiency consequences flow from decisions concerning whether to organize transactions contractually between firms or administratively within them, and that for any given transaction an optimal governance structure exists which depends in a predictable way on certain attributes of the transaction. There are substantial differences in nuclear power plant project organization among the three countries. The transaction cost approach cannot explain why these differences have arisen, since they are much less the outcome of the formal economic optimization process assumed in the theory than of state-specific factors, including industrial traditions, legal restrictions, political initiatives and administrative planning. Nevertheless, the approach provides qualitative insights into the economic implications of these differences. It also provides insights into why an organizational approach that is effective in one structural and/or national cultural context may be more or less effective in another.Mellon Foundation and the M.I.T. Center for Energy Policy Researc