A data warehouse is an integrated and timevarying collection of data derived from operational data and primarily used in strategic decision making by means of online analytical processing (OLAP) techniques. Although it is generally agreed that warehouse design is a non-trivial problem and that multidimensional data models and star or snowflake schemata are relevant in this context, hardly any m...

Nowadays most organizations have incorporated datawarehouses as one of their principal assets for the efficient management of information. It is vital to be able to guarantee the quality of the information that is stored in the datawarehouses given that they have become the principal tool for strategic decision making. The quality of the information depends on the quality of its presentation an...

The efficiency of the scroll compressor which employs the axial and the radial sealing techniques is competitive with that of the other rotary and the reciprocating compressors. The bearing load and the torque are smooth so that quiet operation is realized. 'l'herefore the machine is suitable particularly for air conditioning application. The authors have studied the scroll compressor which uti...

The influence of temperature, mean nanoparticle size and the nanoparticle concentration on the dynamic viscosities of nanofluids are investigated in an analytical method followed by introduction of modified equations for calculating the nanofluids’ viscosities. A new correlation is developed for effective viscosity based on the previous model where the Brownian movement of the nanoparticles is co...

the shape of wake behind a wind turbine is normally assumed to have a hat shape for the models used in wind farm layout optimization purposes; however, it is know from experimental tests and numerical simulations that this is not a real assumption. in reality, the results of actual measurements and detailed numerical simulation show that the velocity in wake region has a s-shape profile. the pr...