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A hysteresis interior permanent-magnet (IPM) motor is a solid-rotor self-starting synchronous motor. Its rotor has a hysteresis ring made of composite material with high degree of hysteresis energy per unit volume. The Neodymium Boron Iron (Nd-B-Fe) magnets are buried inside the hysteresis ring. This paper presents the analytical modeling of a hysteresis IPM motor to investigate its starting and synchronization capability for different loading conditions. A V/F controller has been designed to operate the motor at variable speeds. Simulations have been carried out to obtain the run-up responses of a three-phase four-pole 208 V, 2.5 kW hysteresis IPM motor. Simulation results are presented and analyzed in this paper. Experimental investigations have been carried out for the same 2.5-kW motor. Both the simulation and experimental results are presented in this paper. [ABSTRACT FROM AUTHOR]

The study was conducted to estimate the serum lipid levels in women using depot medroxyprogesterone acetate (DMPA). A total of 90 Bangladeshi married women of age group 15-40 years attending the Model Family Planning Clinic, Mymensingh Medical College Hospital, Mymensingh, from July 2010 to June 2011. Patients were classified into three groups comprising those using the drug for 3 months (n=30), 1 year (n=30), and 2 years (n=30), respectively, compared to a control group (n=30) of married non-hormonally treated women of similar ages. Their age, weight, height, BP and BMI were recorded; all the subjects were clinically examined. Blood samples were collected for biochemical assay of serum lipid profiling parameters, such as total cholesterol, HDL-C, TAG and LDL-C. Data were collected and processed according to the design and objectives of the study. A significant (p<0.01) decrease in serum total cholesterol was observed up to 1 year of using DMPA, but a sharp increase was observed in 2 years group. Likewise total cholesterol, HDL-C was significantly (p<0.01) decreased in the 1 year group and rapidly increased in the 2 years group. A significant (p<0.01) reduction in TAG level was observed throughout the study tenure when compared with control group. No significant (p>0.05) difference in LDL-C level was observed among the treatment groups. The study concludes that DMPA induced significant alterations in lipid profiling parameters of the studied population and prolong use does not have risk of atherosclerosis; however, further study with a larger sample size is suggested for a general recommendation.