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This paper presents a joint experimental and theoretical study of positron scattering from furan. Experimental data were measured using the low energy positron beamline located at the Australian National University and cover an energy range from 1 eV to 30 eV. Cross sections were measured for total scattering, total elastic and inelastic scattering, positronium formation, and differential elastic scattering. Two theoretical approaches are presented: the Schwinger multichannel method and the independent atom method with screening corrected additivity rule. In addition, our data are compared to corresponding electron scattering results from the same target with a number of significant differences observed and discussed.

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There are many pump and motor installations with quite extensive speed variation, such as Sago conveyor, heating, ventilation and air conditioning (HVAC) and water pumping system. A common solution for these applications is to run several fixed speed motors in parallel, with flow control accomplish by turning the motors on and off. This type of control method causes high in-rush current, and adds a risk of damage caused by pressure transients. This paper explains the design and implementation of a temperature speed control system for use in industrial and commercial sectors. Advanced temperature speed control can be achieved by using ABB ACS800 variable speed drive-direct torque sequential control macro, programmable logic controller and temperature transmitter. The principle of direct torque sequential control macro (DTC-SC) is based on the control of torque and flux utilizing the stator flux field orientation over seven preset constant speed. As a result of continuous comparison of ambient temperature to the references temperatures; electromagnetic torque response is particularly fast to the motor state and it is able maintain constant speeds. Experimental tests have been carried out by using ABB ACS800-U1-0003-2, to validate the effectiveness and dynamic respond of ABB ACS800 against temperature variation, loads, and mechanical shocks.

We report measurements of low energy positron scattering from neon, with the first measurements of absolute differential cross sections (DCSs) and of state-selective electronic excitation. These measurements are compared to calculations using the relativistic optical potential (ROP) technique, as well as other recently published theoretical calculations. At the lowest energies, experimental DCS data are fitted to extract scattering phase shifts, which can be compared to theoretical values and also used to generate DCS values over the full angular range. For the most part we find good accord in the two descriptions of the scattering processes, with some key disagreements. An analysis of possible sources of systematic error has also been presented, in light of the discrepancies.