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Virtual reality (VR) systems for guiding remote physical tasks typically require object poses to be specified in absolute world coordinates. However, many of these tasks only need object poses to be specified relative to each other. Thus, supporting only absolute pose specification can create inefficiencies in giving or following task guidance when unnecessary constraints are imposed. We are developing a VR task-guidance system that avoids this by enabling relative 6DoF poses to be specified within subsets of objects. We describe our user interface, including how geometric relationships are specified and several ways in which they are visualized, and our plans for validating our approach against existing techniques. 

Copies (proxies) of objects are useful for selecting and manipulating objects in virtual reality (VR). Temporary proxies are destroyed after use and must be recreated for reuse. Permanent proxies persist after use for easy reselection, but can cause clutter. To investigate the benefits and drawbacks of permanent and temporary proxies, we conducted a user study in which participants performed 6DoF tasks with proxies in the Voodoo Dolls technique, revealing that permanent proxies were more efficient for hard reselection and preferred. 

Entity–Component–System (ECS) architectures are fundamental to many systems for developing extended reality (XR) applications. These applications often contain complex scenes and require intricately connected application logic to connect components together, making debugging and analysis difficult. Graph-based tools have been created to show actions in ECS-based scene hierarchies, but few address interactions that go beyond traditional hierarchical communication. To address this, we present an XR GUI for Mercury (a toolkit to handle cross-component ECS communication) that allows developers to view and edit relationships and interactions between scene entities in Mercury. 

Recent concurrent shifts of the East Asian polar-front jet (EAPJ) and the East Asian subtropical jet (EASJ) in the boreal winter have raised concerns, since they could result in severe weather events over East Asia. However, the possible mechanisms are not fully understood. In this study, the roles of the interdecadal Pacific oscillation (IPO) and the Atlantic multidecadal oscillation (AMO) are investigated by analyzing reanalysis data and model simulations. Results show that combinations of opposite phases of the IPO and AMO can result in significant shifts of the two jets during 1920–2014. This relationship is particularly evident during 1999–2014 and 1979–98 in the reanalysis data. A combination of a negative phase of the IPO (−IPO) and a positive phase of the AMO (+AMO) since the late 1990s has enhanced the meridional temperature gradient and the Eady growth rate and thus westerlies over the region between the two jets, but weakened them to the south and north of the region, thereby contributing to the equatorward and poleward shifts of the EAPJ and EASJ, respectively. Atmospheric model simulations are further used to investigate the relative contribution of −IPO and +AMO to the jet shifts. The model simulations show that the combination of −IPO and +AMO favors the recent jet changes more than the individual −IPO or +AMO. Under a concurrent −IPO and +AMO, the meridional eddy transport of zonal momentum and sensitive heat strengthens, and more mean available potential energy converts to the eddy available potential energy over the region between the two jets, which enhances westerly winds there.