In remote Multi-user AR (MuAR), a user shares with remote users his/her physical environment, which is enhanced by computer-generated perceptual information. Despite its important role in Metaverse, a user may have serious privacy concerns for MuAR: the user may want to share only a portion, or may want to block certain areas in their environment. Today's object detection and AR tracking techniques fall short of reliably, efficiently, and accurately supporting this use case, in particular on an (already overloaded) headset without offloading to an edge/cloud server for privacy preservation purposes.

The paper describes a particular type of self-designed test system for the measurement of thermal protective performance (TPP) of fire protective clothing. A 2nd degree burn curve in human tissue is used as a criterion to rate the performance of clothing materials. It is known that the quality of fire protective clothing, esp. the thermal protective performance is of great significance to the lives of firefighters. The TPP test system thus developed is the first and the only one of its kind in China, the specifications of which can meet all the corresponding technical requirements of the Standard GA10-2002 "Protective Clothing for Firefighters" issued by Ministry of Public Security of the People's Republic of China. The configuration of the test system and the mechanism of the measurement are presented. In addition, the comparisons of the test results and the applications of TPP test are also presented

The displacement measurement of capacitive transducers of both variable square types and variable clearance types is generally limited in a range of several millimeters to several centimeters. For the measurement of large displacement over 100mm, mainly the measuring devices such as inductorsyn and optical grating are used. It is difficult to use such measuring systems widely for the reason that they have a complex electronic circuit of high cost and high consumption of energy, and it is difficult to integrate the circuit. However, a particular type of capacitive device for large displacement measurement has found its wide application. It is very convenient to apply it widely to both a digital electronic caliper and the displacement measurement of a machine because it eliminates the drawbacks of the aforementioned systems. The paper simply describes the principle of the new capacitive transducer and its measuring system. The error sources of the system are discussed and the methods to reduce it or to improve the measurement accuracy are presented. The result of the experiment is the same as that of the theoretical analysis