Timothy E. Wright

Learn More
The authors report the results of an indirect comparison of the standards of absorbed dose to water in high-energy photon beams from a clinical linac and (60)Co radiation beam performed between the National Metrology Institute of Japan (NMIJ) and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). Three ionisation chambers were(More)
The absolute dose delivered to a dynamically scanned sample in the Imaging and Medical Beamline (IMBL) on the Australian Synchrotron was measured with a graphite calorimeter anticipated to be established as a primary standard for synchrotron dosimetry. The calorimetry was compared to measurements using a free-air chamber (FAC), a PTW 31 014 Pinpoint(More)
The ARPANSA calibration service for (60)Co gamma rays is based on a primary standard graphite calorimeter that measures absorbed dose to graphite. Measurements with the calorimeter are converted to the absorbed dose to water using the calculation of the ratio of the absorbed dose in the calorimeter to the absorbed dose in a water phantom. ARPANSA has(More)
Both proprietary and open source collaborative virtual environments (CVEs) offer extensive means for social, scientific, and commercial collaboration. To safeguard the objects and activities that comprise these virtual worlds, we have proposed, elsewhere, an in-world discretionary access control (DAC) system called WonderDAC. The simplicity and role-based(More)
The use of discretionary access control (DAC) within collaborative virtual environments (CVEs) has been a limited endeavor for both proprietary and open source systems. Yet, as virtual worlds become more useful and engaging to our computing society, the need to safeguard access to virtual objects (e.g., spaces, three-dimensional assets, two-dimensional(More)
In the realm of emergency operations, planning and training is a critical ingredient for success. The use of virtual environments can offer a convenient means of practicing and simulating activities in an emergency operations center (EOC). Although many virtual environments strive to offer realism in their simulations of weather, population, and incident(More)