Detection of a weak magnetic field via cavity enhanced Faraday rotation

We study the sensitive detection of a weak static magnetic field via Faraday rotation induced by an ensemble of spins in a bimodal degenerate microwave cavity. We determine the limit of the resolution for the sensitivity of the magnetometry achieved using either single-photon or multiphoton inputs. For the case of a microwave cavity containing an ensemble of Nitrogen-vacancy defects in diamond, we obtain a magnetometry sensitivity exceeding 0.5~\text{\nano\tesla}/\sqrt{\text{\hertz}}, utilizing a single photon probe field, while for a multiphoton input we achieve a sensitivity about 1 \text{\femto\tesla}/\sqrt{\text{\hertz}}, using a coherent probe microwave field with power of P_\text{in}=1~\text{\nano\watt}.Comment: 8 pages, 7 figure

Design Strategy and Case Study of Distributed System Resilience in Chinese Context

Whether it is a large-scale complex challenge or a radical change, it is calling for a more resilient and sustainable socio-technical system. Distributed system is a new trend of sustainable transition of socio-technical system. The research on related design strategies of distributed systems can help us better understand the nature of distributed systems, the role of designers, and help designers more calmly deal with future related challenges. This paper has conducted an in-depth understanding and discussion on the resilience of soico-technical systems and the relationship between distributed systems and resilience. We selected three representative cases, combined with a series of response measures taken by China in Wuhan during COVID-19 to analyze. Three types of distributed system design strategies suitable for China are identified

Flowmeter for large-scale pipes

AbstractThis paper studied a new type of flowmeter, the bypass flowmeter. It is suitable for large-scale pipes. The principle of bypass flowmeter is studied by analyzing flowing in parallel pipes and carrying out experiments at a modified performance test system for centrifugal pumps. The study results showed that the flowrate ratio between the main pipe and the bypass pipe is determined by the geometric structures of pipes and the flowing states in the pipes. The flowrate ratio varies greatly when the Reynolds numbers are relatively lower both in the main pipe and the bypass pipe. The flowrate ratio keeps constant when the Reynolds number in the main pipe is larger than 120000. The head loss becomes smaller when the bypass pipe is connected to the main pipe. The percentage of head loss decrease is from 7.64% to 9.34%. The results indicate that bypass flowmeter is suitable for flowrate measuring in large scale pipes. It will not cause additional head loss to the flow

Enhancing Students' Metacognition via AI-Driven Educational Support Systems

As the penetration of digital technology deepens and the demands for educational modernization grow, attention is increasingly being drawn towards the application of artificial intelligence (AI) in the field of education. Especially in educational practice, the optimization of students’ learning experiences and the enhancement of their metacognitive abilities through AI technology have captivated the interest of numerous educators and scholars. Metacognition, which represents a core skill in student self-regulation and self-management, has a significant impact on student learning outcomes and quality. However, current educational support systems primarily rely upon traditional methods of data collection and analysis, which have limitations in terms of real-time responsiveness, granularity, and comprehensiveness. The present research aims to investigate the integration of AI technology with a specific focus on the learning process through educational support systems and the development of a cooperative teaching interaction model. This will ultimately enhance the development of students’ metacognitive abilities more effectively