A stability study and moral analysis of a space-station - Centrifuge configuration

Dynamic stability of space station-centrifuge configuratio

The optimization of force inputs for active structural acoustic control using a neural network

This paper investigates the use of a neural network to determine which force actuators, of a multi-actuator array, are best activated in order to achieve structural-acoustic control. The concept is demonstrated using a cylinder/cavity model on which the control forces, produced by piezoelectric actuators, are applied with the objective of reducing the interior noise. A two-layer neural network is employed and the back propagation solution is compared with the results calculated by a conventional, least-squares optimization analysis. The ability of the neural network to accurately and efficiently control actuator activation for interior noise reduction is demonstrated

There\u27s little to choose between scarifier points

Tests on scarifier points showed that methods of treating them to prolong their life had little effect

An evaluation of active noise control in a cylindrical shell

The physical mechanisms governing the use of active noise control in an extended volume of a cylindrical shell are discussed. Measured data was compared with computer results from a previously derived analytical model based on an infinite shell theory. For both the analytical model and experiment, the radiation of the external monopoles is coupled to the internal acoustic field through the radial displacement of the thin, elastic cylindrical shell. An active noise control system was implemented in the cylinder using a fixed array of discrete monopole sources, all of which lie in the plane of the exterior noise sources. Good agreement between measurement and prediction was obtained for both internal pressure response and overall noise reduction. Attenuations in the source plane greater than 15 dB were recorded along with a uniformly quieted noise environment over the entire length of the experimental model. Results indicate that for extended axial forcing distributions or very low shell damping, axial arrays of control sources may be required. Finally, the Nyquist criteria for the number of azimuthal control sources is shown to provide for effective control over the full cylinder cross section

SUSY and Dark Matter Constraints from the LHC

The ability of the LHC to make statements about the dark matter problem is considered, with a specific focus on supersymmetry. After reviewing the current strategies for supersymmetry searches at the LHC (in both CMS and ATLAS), some key ATLAS studies are used to demonstrate how one could establish that SUSY exists before going on to measure the relic density of a neutralino WIMP candidate. Finally, the general prospects for success at the LHC are investigated by looking at different points in the MSSM parameter space.Comment: Talk given at the XLIrst Rencontres de Moriond session devoted to Electroweak Interactions And Unified Theories in March 2006, to be published in the associated proceedings. 10 pages, 8 figure

How efficient are seeding operations : Kondinin work study

The efficiency of machinery and labour during seeding operations was studied in 1977 by the Kondinin and Districts Farm Improvement Group and the Department of Agriculture. The aim was to find what influenced efficiency during cropping. Time spent on activities during the working day was measured, and it was found that repairs, maintenance, meals and other incidental jobs considerably reduced the time spent driving the tractor. Each farmer participating in the study was given the results of his own farm compared to the group, indicating tasks most needing improvement

Brain barriers and brain fluid research in 2016: advances, challenges and controversies

Abstract This editorial highlights some of the advances that occurred in relation to brain barriers and brain fluid research in 2016. It also aims to raise some of the attendant controversies and challenges in such research.http://deepblue.lib.umich.edu/bitstream/2027.42/136059/1/12987_2017_Article_52.pd