let a; b; k 2 k and u ; v 2 u(k). we show for any idempotent e 2 k, ( a 0 b 0 ) is e-clean i ( a 0 u(vb + ka) 0 ) is e-clean and if ( a 0 b 0 ) is 0-clean, ( ua 0 u(vb + ka) 0 ) is too.

An analysis of the chemical composition between 300 and 1000 TeV based on the uctuation of the shower maximum using data from the AIROBICC and scintillator array of the HEGRA installation is presented. Within the errors the composition is in agreement with the low energy composition over the whole energy range. The chemical composition beyond about 100 TeV will provide a decisive clue about cos...

In τ physics, we are at the frontier between the completion of the LEP program and the start of analyses from b-factories, which are expected to produce results in the coming years. Nice results from CLEO are steadily delivered in the meantime. For charm, impressive progress have been achieved by fixed target experiments in the search for CP violation and D • − D • oscillations. First results f...

Renewable energy can help to tackle energy poverty issues of the availability of modern energy services and the sustainability of energy supply. Based on the concept of the Energy Development Index, published by International Energy Agency, this paper builds the clean energy development index and applies the Grey incidence decision method to analyze regional energy poverty issues in China. A mo...

Abstract The United States has experienced heightened interest in clean energy sources, with many states implementing renewable technologies for generation. These efforts are critical moving and the nation toward decarbonization decreased emissions within transportation power industries. A challenge sources (particularly solar wind) is inherent variability of generation due to climate geographi...

As global warming has become an issue that all human beings have to address, it is time to figure out how to reform our power system such that we can reduce the CO2 emission meanwhile stimulating the development of clean energy, such as wind energy. Because wind energy is not so dispatchable as fossil energy and it is always located in remote areas far away from high-power-demand areas, it is n...

Glycerol is a by-product of biodiesel obtained from biomass, accounting for 10% of the biodiesel production. In the context of a green economy, aiming for a reduction of the emission of atmospheric greenhouse gases emissions, the demand of biodiesel is expected to increase vastly, in parallel with a side glut supply of glycerol. Given the high cost of biodiesel compared with its fossil congener...

We perform a comparative study of two methods of determining the survival probabilities of low, intermediate, and high energy solar neutrinos that emphasizes the general agreement between the Large Mixing Angle (LMA) solution and extant solar neutrino data. The first analysis is oscillation parameter-independent and the second analysis involves an approximate calculation of the survival probabi...