in direct torque control, the selection of an applied voltage vector is based on the measuredparameters at the beginning of the sampling period. the delay between the measurement and the application of the voltage vector is the origin of an extra torque ripple. in this paper, a new predictive controller is proposed for compensating this delay and reducing the torque ripple. the stator current i...

Walter W. Kovalick, Jr., Ph.D. Director An emerging technology for the remediation of ground water is the use of microorganisms to degrade contaminants which are present in aquifer materials. Understanding the processes which drive in-situ bioremediation, as well as the effectiveness and efficiency of the utilization of these systems, are issues which have been identified by the Regional Superf...

Reactive zero valent iron nanoparticles can degrade toxic nonaqueous phase liquids (NAPL) rapidly in contaminated groundwater to nontoxic products in situ, provided they can be delivered preferentially to the NAPL/water (oil/water) interface. This study demonstrates the ability of novel triblock copolymers to modify the nanoiron surface chemistry in a way that both promotes their colloidal stab...

the simultaneous flow of oil and water in porous media is described by relative permeability curves, mainly derived from laboratory experiments. relative permeability is of paramount importance in predicting reservoir production performance and drive mechanisms and its value depends largely on the volume fraction of fluids present in the test samples. nowadays x-ray scanners are one of the most...

Water the solvent of life plays an important role in biological assembly and organization. Folding of proteins, formation of micelles and membranes, and molecular recognition in biological systems are all 'water-mediated' processes, in which molecular structure and organization of water can drive thermodynamics and guide the mechanics of assembly. However, understanding the molecular details of...

A new type of pulsed water jet, which uses principles of self-resonance to create pressure fluctuations, is now being developed. The advantages of pulsing to improve the erosive action of a jet—by interrupting the flow, hence using the water hammer impact stress created by each individual slug—have long been appreciated by the users of water jets for cutting and cleaning applications. Of severa...

Displacement of oil and water in porous media of reservoir rocks is described by relative                      permeability curves, which are important input data for reservoir performance simulation and drive mechanism studies. Many core studies, such as multiphase relative permeability, capillary pressure and saturation exponent determination, depend on the volume fractions of multiphase flui...