PHASE-SENSITIVE AND DUAL-ANGLE RADIOFREQUENCY MAPPING IN NA MAGNETIC RESONANCE IMAGING Steven P. Allen Department of Physics and Astronomy Bachelor of Science Many diagnostic applications in sodium magnetic resonance imaging (MRI) require accurate flip angle mapping. In search for a mapping technique that performs well in sodium MRI, we evaluated the low signal-to-noise ratio performance of the...

Objective(s)Bioelectrical impedance is the measure of impedance of the body. Impedance consists of electric resistance and reactance. Phase angle (PA) is the tan value of the ratio of reactance versus electric resistance. PA depends on cell membrane integrity and on body cell mass. There exists a correlation between PA values and body cell mass.The objective of this study was to compare the PA ...

For lifting entry vehicle, angle of attack is one of the most important trajectory control inputs. This paper aims to develop a practical and effective method for angle of attack design. First, the factors which impact angle of attack are analyzed. The entry flight is discussed as equilibrium glide phase and initial diving phase respectively. And the operation zone of angle of attack is obtaine...

the manner of spray the fuel has an important effect on stability and convenient mixture of fuel and oxidizer. swirl injectors because of formation of uniform spray cone and proper distribution of the fuel have been used in many rocket engines at aerospace industries. formation and development of air core in the interior stream of swirl injectors and simulation of them is complicated. double ba...

Current engineering practice for adaptive control schemes is to base the design on globally convergent schemes for simple plant models, An important class of such schemes uses least squares estimation of assumed simple input–output models and constructs the controller using the parameter estimates. This paper studies the robustness of such schemes to the presence of unmodelled plant colourcd no...

AIM Evaluate the association between phase angle and the development of hepatic encephalopathy in the long-term follow-up of cirrhotic patients. METHODS This was a prospective cohort study. Clinical, nutritional and biochemical evaluations were performed. Mann-Whitney's U and χ2 tests were used as appropriate. Kaplan-Meier curves and Cox proportional Hazards analysis were used to evaluate the...

National Bureau of Standards Gaithersburg, MD 20899 To provide a phase meter calibration service, a phase angle calibration standard has been developed at NBS. This standard is a signal. generator with two sinusoidal outputs and uses direct digital synthesis to generate the signals. The phase angle between the two sinusoids is determined by the input parameters in the calculation of the sets of...