3D Virtual Worlds and the Metaverse: Current Status and Future Possibilities

Moving from a set of independent virtual worlds to an integrated network of 3D virtual worlds or Metaverse rests on progress in four areas: immersive realism, ubiquity of access and identity, interoperability, and scalability. For each area, the current status and needed developments in order to achieve a functional Metaverse are described. Factors that support the formation of a viable Metaverse, such as institutional and popular interest and ongoing improvements in hardware performance, and factors that constrain the achievement of this goal, including limits in computational methods and unrealized collaboration among virtual world stakeholders and developers, are also considered

Statistical Short-Range Guidance for Peak Wind Speed Forecasts at Edwards Air Force Base, CA

The peak winds near the surface are an important forecast element for space shuttle landings. As defined in the Flight Rules (FR), there are peak wind thresholds that cannot be exceeded in order to ensure the safety of the shuttle during landing operations. The National Weather Service Spaceflight Meteorology Group (SMG) is responsible for weather forecasts for all shuttle landings, and is required to issue surface average and 10-minute peak wind speed forecasts. They indicate peak winds are a challenging parameter to forecast. To alleviate the difficulty in making such wind forecasts, the Applied Meteorology Unit (AMU) developed a PC-based graphical user interface (GUI) for displaying peak wind climatology and probabilities of exceeding peak wind thresholds for the Shuttle Landing Facility (SLF) at Kennedy Space Center (KSC; Lambert 2003). However, the shuttle occasionally may land at Edwards Air Force Base (EAFB) in southern California when weather conditions at KSC in Florida are not acceptable, so SMG forecasters requested a similar tool be developed for EAFB

Use of CO\u3csub\u3e2\u3c/sub\u3e Concentration Difference or CO\u3csub\u3e2\u3c/sub\u3e Balance to Assess Ventilation Rate of Broiler Houses

Ventilation rate (VR) is one of the two key elements for quantifying aerial emissions from animal production facilities. Direct, continuous measurement of building VR can be challenging and impractical under certain circumstances,e.g., naturally ventilated animal housing or a large number of ventilation fans in the building. This study examined the suitability of estimating VR of broiler houses with built‐up litter (mixture of manure and bedding), when supplemental heating was not in use, through either carbon dioxide (CO2) balance or the relationship of VR to CO2 concentration difference between exhaust and inlet air. The reference VR was based on direct measurement by continuously monitoring operation of the in‐situ calibrated exhaust fans. The comparative analysis of the direct method vs. each indirect method was conducted for a measurement integration time (MIT) of 10, 30, 60, or 120 min. The analyses revealed that MIT of 30 min or greater resulted in non‐significant differences in VR between the indirect and direct methods. The broiler building VR (m3 s‐1) may be related to the exhaust‐inlet CO2 concentration difference (ΔCO2, ppm) as VR (±3.0) = 4456 (±41) ΔCO2‐0.786 (±0.019) at 30 min MIT. The VR may also be determined by the CO2 balance method (including litter CO2 generation) with a correction factor of 0.97 at MIT of 30 to 120 min. If litter CO2 generation is omitted from the total building CO2 production, the actual VR may be estimated by applying a correction factor of 1.077 to the bird respiration CO2 balance VR. Hence, the CO2balance or concentration difference method offers a viable alternative or supplemental check for quantifying building VR under certain conditions where direct, continuous VR measurement is not feasible