Abstract: A method for determining airborne concentrations of an ensemble of particulate matter below the size fraction 2.5 ?m in aerodynamic diameter (PM2.5). The method is to be composed of a sharp cut PM2.5 cyclone, optical sensor capable of producing scattering coefficients dependent on particle size, temperature and humidity sensors for adapting to changes in the environment, and a processing system for applying logic-based algorithm to convert raw sensor values into PM concentrations. The optical sensor is a dual wavelength integrating nephelometer capable of yielding particle characteristic scattering coefficients at two wavelengths. The particle scattering ratios between two wavelengths are used in conjunction with temperature and humidity in the method's algorithm to reduce particle growth bias and to ultimately yield PM2.5 concentrations.

Abstract: The present invention provides a method and apparatus for completing a transaction using a wireless mobile communication channel and another communication channel, particularly another communication channel that provides for near field radio channels (NFC), as well as other communication channels, such as Bluetooth or WIFI. The present invention also provides a method of completing a transaction in which a management server assists a transaction server and a point of sale terminal in forwarding transaction information to a hand-held mobile device, with the transaction having originated from the hand-held mobile device. There is also provided a hand-held mobile device that wirelessly communicates between a secure element and a radio element that are associated with the hand-held mobile device.

Abstract: The present invention provides a method and apparatus for completing a transaction using a wireless mobile communication channel and another communication channel, particularly another communication channel that provides for near field radio channels (NFC), as well as other communication channels, such as Bluetooth or WIFI. The present invention also provides a method of completing a transaction in which a management server assists a transaction server and a point of sale terminal in forwarding transaction information to a hand-held mobile device, with the transaction having originated from the hand-held mobile device. There is also provided a hand-held mobile device that wirelessly communicates between a secure element and a radio element that are associated with the hand-held mobile device.