Solar pumped laser

A solar pumped laser is described in which the lasant is a gas that will photodissociate and lase when subjected to sunrays. Sunrays are collected and directed onto the gas lasant to cause it to lase. Applications to laser propulsion and laser power transmission are discussed

Space shuttle: Supersonic aerodynamic characteristics of the MSC 040A orbiter (M equals 2.0 to 4.0)

A wind tunnel test of the space shuttle orbiter configuration 040A was run in a 20 in. supersonic wind tunnel. Basic aerodynamic data for this vehicle were determined at Mach 2.0, 2.4, 3.0 and 4.0

Energy Spectrum Evolution of a Diffuse Field in Elastic Body Caused by Weak Nonlinearity

We study the evolution of diffuse elastodynamic spectral energy density under the influence of weak nonlinearity. It is shown that the rate of change of this quantity is given by a convolution of the linear energy at two frequencies. Quantitative estimates are given for sample aluminum and fused silica blocks of experimental interest.Comment: 9 pages, 3 figures; revised for better presentatio

Development and initial operating characteristics of the 20 megawatt linear plasma accelerator facility

A 20-megawatt linear plasma accelerator facility, a steady flow, Faraday-type plasma accelerator facility for high velocity aerodynamic testing, was constructed, developed, and brought to an operational status. The accelerator has a 63.5-mm-square and 0.5-meter-long channel and utilizes nitrogen-seeded with 2 % mole fraction of cesium vapor. Modification of the original accelerator design characteristics and the improvements necessary to make the arc heater a suitable plasma source are described. The measured accelerator electrode current distribution and the electrode-wall potential distributions are given. The computed and the measured values are in good agreement. Measured pitot pressure indicates that an accelerator exit velocity of 9.2 km/sec, is obtained with 30 of the 36 electrode pairs powered and corresponds to a velocity increase to about 2 1/4 times the computed entrance velocity. The computed stagnation enthalpy at the accelerator exit is 92 MJ/kg, and the mass density corresponds to an altitude of about 58 km. The 92 MJ/kg stagnation enthalpy corresponds to a kinetic energy content at low temperature equivalent to a velocity of 13.6 km/sec

Research on a one-inch-square linear d-c plasma accelerator

One-inch-square linear d-c plasma accelerator using cesium seeded nitroge

A preliminary training guide for utilizing high-altitude, color-infrared photography in compiling soil maps

Instruction for acquiring and analytically processing small-scale color-infrared photography to perform a soil resources inventory over forests of the southern U.S. is provided. Planning the project; acquiring aerial photography, materials, equipment and supplemental data; and preparing the photography for analysis are discussed. The procedures for preparing ancillary and primary component overlays are discussed. The use of correlation charts and dichotomous keys for mountain landforms, water regime, and vegetation is explained

Dairy Price commodity in Italy: volatility and forecast after milk quotas

The EU dairy industry is facing an unprecedented change since the removal of milk quotas has exposes the sector to the world competition with strongly organized multinational traders. The basic question of this paper is if the milk quota expiration will have any impact on market equilibria and decisions of agents operating at various market levels. This paper has been preceded by two other papers discussing various issues about dairy market in Italy: market asymmetries and consequences for price transmission and presence of oligopoly competition and consequences for price setting. The present analysis uses the time series analysis of weekly dairy prices to test the market behavior before and after quota regime. Volatility was tested with simple CV, SD indexes and more complexes Arch-Garch models including the breaks and changes in market regime correlated to policy adjustments. Results suggest a moderate change in volatility; our explanation is the Italian dairy sector was for long time protected from world market competition and a consistent amount of raw milk processed for cheese production was managed by the coop organization that transferred to the dairy farms the margins realized at other market levels. The future scenario is more pessimistic in absence of any protection: some structural changes needed to face the world competition could have been postponed in this protected market with the OCM. The expected growth of milk supply after quota will determine a decline in the raw milk price becoming closer to the marginal costs of the most efficient dairy farms in the world. This will cause the exit of a great number of dairy farms, the restructuring of the dairy industry and more concentration at retail level

Price Transmission in Vertical Dairy Chains: The Italian Case

At a theoretic level, price transmission does not provide a clear signal of competitiveness as many conditions may induce stickiness and even asymmetry in the speed of adjustment to positive and negative changes. While evidence from past EU studies for the dairy sector is mixed, several studies have found evidence of asymmetry in particular countries. However, none to our knowledge have considered evidence for Italy. We examine price dynamics within the chain and test for presence of asymmetry in the transmission of price changes along the chain. Using a parametric test of asymmetry in a multivariate VECM, we find strong evidence of symmetry in co-movement. To explore whether these results are robust with respect to nonlinearity we estimate threshold VECM models and also find strong evidence to reject asymmetry except for the transmission between raw milk and wholesale butter prices. While inference with respect to competitiveness of markets cannot be inferred from evidence of asymmetry, findings of symmetry confirm that the market organization and performance is not controlling price change to be asymmetric

Arabian Moon

https://digitalcommons.library.umaine.edu/mmb-vp/4995/thumbnail.jp