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Your search keyword '"Duan, Haoran"' showing total 227 results
Start Over Author "Duan, Haoran" Publication Type Academic Journals
227 results on '"Duan, Haoran"'

11. Risk assessment and prediction of critical mineral resources supply for China: A case of copper

Author

CHENG Jinhua, SHUAI Jing, ZHAO Yujia, DUAN Haoran, SHUAI Chuanmin

Subjects
critical minerals, copper resources, supply risk, evaluation and prediction, international competitiveness, smaa-tri, Environmental sciences, GE1-350, Biology (General), QH301-705.5
Abstract

[Objective] In today’s world, global risks have increased dramatically, and critical mineral resources are no exception. What are the supply risks of critical minerals for China and how should China deal with the increasing risks of critical mineral resources supply? [Methods] To answer these questions, we established an evaluation and prediction indicator system of environment-market-resource-competitiveness (EMRC) for assessing the supply risks of critical mineral resources by introducing an international competitiveness index, evaluated the supply risk of copper resources in China from 2008 to 2021 by using the stochastic multicriteria acceptability analysis (SMAA-TRI) method, and predicted the supply risk of copper resources in China by adopting the back propagation (BP) neural network. [Results] The results show that: (1) The international competitiveness dimension had the greatest impact on China’s copper supply risk, while the environmental dimension had the least impact; (2) From the perspective of the overall supply risk of copper resources, China’s risk is generally in the medium-high to high range, with a rising trend year by year; (3) From 2022 to 2023, the predicted value of China’s copper resources supply risk is medium-high. [Conclusion] To enhance the security of copper resources supply, China should increase investment in copper exploration, improve the utilization rate of domestic copper resources, strengthen resource diplomacy, and diversify import sources.

Published
2023
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48. A portable frequency‐domain electromagnetic detection system.

Author

Peng, Fengjiang, Zhao, XueZhao, Zhang, Song, Duan, Haoran, Du, Shibao, Zhao, Qing, and Guo, Cheng

Subjects
TRANSMITTERS (Communication), PULSE width modulation, DIGITAL modulation, GEOPHYSICAL prospecting
Abstract

Summary: Frequency‐domain detection stands as a critical method in remote geophysical exploration; however, its practical application is constrained by the considerable size of the requisite instrumentation. In this paper, we present a compact frequency domain electromagnetic detection system. The integration of intelligent power devices and a novel hardware architecture substantially diminishes the system's dimensions, thereby enhancing its portability. Furthermore, the system design incorporates sinusoidal pulse width modulation and digital phase‐locked amplification to ensure the efficacy of the proposed system. Both the transmitter and receiver system are constrained to dimensions smaller than 1.5 m. Subsequent experimental validation attests to the exemplary hardware performance of the proposed system, with the transmitting voltage of the transmitter circuit attaining 500 V, and the receiver circuit exhibiting a sensitivity as low as 10−8 V. Significantly, this design paradigm not only facilitates the integration of transmitter and receiver systems for frequency‐domain electromagnetic detection but also introduces novel prospects for the application of frequency‐domain electromagnetic detection methods across diverse fields. [ABSTRACT FROM AUTHOR]

Published
2024
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