On the theory of 3-phase squirrel-cage induction motors includingspace harmonics and mutual slotting

General equations for squirrel-cage induction motors are derived based on the real geometry of the motor. The squirrel cage is described by its meshes; no equivalent windings are used. By means of complex time-dependent transformations free angles are introduced which simplify the set of equations when the specific geometrical properties of both types in which the asynchronous machines fundamentally can be divided are taken into account. The equations are general in the sense that all space harmonics are taken into account, due to the MMF and double slotting. This provides a better calculation of the synchronous, pulsating, and asynchronous torques. The final equations enable the formulation of some specific properties of both types in connection to their electromechanical behavior. Further, they are valid for star and delta connections and for any arbitrary source voltage     

Ionic Channels as Natural Nanodevices

Ion channels are proteins with a hole down their middle important in a wide range of biological functions yet simple enough to be analyzed as devices in the engineering tradition.     

Strengthening national capital: a postcolonial analysis of lifelong learning policy in St Lucia, Caribbean

This paper provides a postcolonial policy analysis of the Education Sector Development Plan: 2000-2005 and Beyond in the small Caribbean island nation of St Lucia. The specific focus is upon the nature of the lifelong learning policy as incorporated in the Plan. This is shown to be a globalised policy discourse. Drawing on a number of postcolonial theorists, the paper works with a concept of the postcolonial as an aspirational politics. Bourdieu's concept of 'national capital' is also utilised in the analysis in relation to the attempt to manage some autonomy for the nation in the process of policy text production in education. The analysis demonstrates the way a postcolonial politics, manifest as strengthening national capital, worked in relation to the production of the Plan in its consultative mode of production and in its extensive cross-sector coverage. However, the analysis also shows evidence of the effects of residues of the colonial past in the hegemony of English in the Plan's recommendations, in the restriction of lifelong learning facilitation to schools and in the denial of a place for indigenous knowledges. The mode of lifelong learning supported is also dominated by a human capital framework and neglect of other capitals (social, cultural, etc.) for constituting what might be seen as a postcolonial and creole learning society. The paper also reflects upon the extent of the postcoloniality of the analysis provided.     

Information Assurance Technology Forecast 2008

A virtual roundtable (featuring panelists Steven Bellovin, Terry Benzel, Bob Blakely, Dorothy Denning, Whitfield Diffie, Jeremy Epstein, and Paulo Verissimo) discussing the next 15 years in computer security.     

解读RFID六大关键趋势

回首过去,我们发现在RFID的发展方面,2006年已经成为"一方面与另一方面"的一年.     

Laboratory simulated slipstream testing of novel sulfur removal processes for gasification application

The Wabash River Integrated Methanol and Power Production from Clean Coal Technologies (IMPPCCT) project is investigating an Early Entrance Coproduction Plant (EECP) concept to evaluate integrated electrical power generation and methanol production from coal and other carbonaceous feedstocks. Research, development and testing (RD&T) that is currently being conducted under the project is evaluating cost effective process systems for removing contaminants, particularly sulfur species, from the generated gas which contains mainly synthesis gas (syngas), CO₂ and steam at concentrations acceptable for the methanol synthesis catalyst. The RD&T includes laboratory testing followed by bench-scale and field testing at the SG Solutions Gasification Plant located in West Terre Haute, Indiana. Actual synthesis gas produced by the plant was utilized at system pressure and temperature for bench-scale field testing.