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Muography is a rapidly developing and non-destructive tomographic technology that uses cosmic ray muons. Due to the natural presence and deeper penetration of cosmic ray muons, scientists have performed various pioneer studies in fields, such as customs security, the internal imaging of volcanoes, scientific archaeology, and others. With unique advantages, muography has gained increasing attention from archaeologists as a novel and innovative tool to investigate large-scale archaeological sites. This approach may be especially helpful for identifying endangered cultural relics and monuments. In the work, we employ a compact, rugged, and portable muon imaging system, CORMIS (COsmic Ray Muon Imaging System), deployed at up to six measurement locations to perform a case study of three-dimensional muography in Xi’an city, China. Cultural cities, such as Xi’an, have long histories and could benefit from innovative techniques used to investigate, conserve, and protect large historical sites. In this paper, we present in detail a high resolution survey on a rampart of a Xi’an defensive wall in demand of urgent protection. The survey data are carefully processed with advanced statistical methods newly introduced in muography, and the results indicate density anomalies inside the rampart with unprecedented levels of precision. The density anomalies are potential safety hazards and need to be eliminated as soon as possible. The successful implementation of this survey significantly encourages more engagement on the tangible application of high-precision 3D muography in archaeological investigations and protection projects around the world.

In response to the worldwide shortage of 99mTc supply caused by the combined consequence from both decommissioning and maintenance of research reactors worldwide, the Institute of Modern Physics (IMP) of the Chinese Academy of Science and Lanzhou University have launched a collaboration to research and develop a 99mTc production solution based on the 25 MeV high-intensity superconducting proton linear accelerator. Radiation from high-current proton bombardment must be evaluated and considered carefully at the design stage to meet radiation protection (RP) policy and requirements of the shielding for the key device. This work employed FLUKA to conduct the shielding assessment of both prompt and residual radiation fields in several iterations, based on a prototype of the high-power target system. The prompt dose rates outside the target station are lower than the institution’s limit. The residual dose rates inside the station fall below 100 μSv/h at 64 h after the end of beam (EOB); the dominant source term is then the target chamber. The service life of the main actuator is expected to be extended by 2.7 times with the current partial shielding design. The simulation accelerating techniques are applied to balance the accuracy of results and the progress of the project at the same time, which is referential to the shielding assessment of large-scale nuclear facilities. The results can also be used in further study and construction of the target station.

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The requirement of modern power grid for distribution automation is becoming more and more stringent and standardized. Aiming at the situation that the large number of distribution automation terminal units brings to for a lot of inconvenience of maintenance work, this paper establishes a state evaluation system of distribution automation terminal unit based on AHP, and designs a software platform for the system. The software platform occupies little memory, and has friendly interface and is simple. It only needs to input the state of the terminal unit to get the evaluation level of the terminal unit. The software platform can also modify the weight score of each index according to the evaluation results, to constantly revise the judgment matrix and evaluate the terminal more accurately. It provides a reference for terminal state control of distribution automation.