Abstract: An apparatus and method for controlling humidification device turndown ratio for proton exchange membrane fuel cells includes a proton exchange membrane fuel cell, a humidifier, a water separator for directing water vapor from the proton exchange membrane fuel cell to the humidifier, a bypass valve to regulate vapor flow into the humidifier, a turbo-compressor and control valve for regulating temperature of air flow into the humidifier, and an expansion turbine for recovery of energy from the humidifier and bypass valve.

Abstract: An apparatus for making a bioprosthetic stent graft is disclosed, the stent having a stent frame and a biomaterial sheath suturelessly bonded to the stent frame. An automated energy irradiator guidance system is disclosed which reduces the potential for human error and improves the consistency and repeatability of tissue welding techniques. The system includes a mapper, a patternizer, an energy director and can additionally include an energy regulator. An interface is included, allowing pattern creation, selection and editing by a user. The system further provides control of energy irradiator parameters for use in tissue welding.