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16. Zonal prevention and control technology for rock burst in asymmetrical pressure-relief working face under protective layer

Author

OUYANG Zhenhua, ZHOU Ranran, SHI Zengzhu, YI Haiyang, YANG Yong, WANG Qi, MA Hongjun, DING Wei

Subjects
protective layer, asymmetrical pressure-relief, rock burst, zone prevention and control, numerical simulation, coal pillar, Mining engineering. Metallurgy, TN1-997
Abstract

In order to effectively prevent and control the rock burst in the asymmetric pressure-relief working face under protective layer, taking the 0291 working face of Tangshan Coal Mine as the engineering background, the theoretical analysis and numerical simulation methods were adopted, and the potential influence factors of rock burst in the working face and the occurrence area were analyzed. The results show that the mining depth, bursting tendency of coal seam and its roof, residual pillars in upper protective layer and goaf of the coal seam and thick and hard roof are the potential influence factors of rock burst. Before mining, under the influence of the residual pillars in the protective layer and goaf, the stress of the two tunnels in the 0291 working face shows an asymmetrical distribution. The high stress area of the return airway is mainly located below the cutting line and stop line of the 0250 goaf, while the high stress area of the transportation roadway is mainly located below the cutting line of the 0251 goaf. The working face had obvious zonal characteristics. In the early stage of mining, the advanced stress in surrounding rock of transportation roadway is higher than that of return airway. It is necessary to strengthen the monitoring of transportation roadway and take pressure-relief measures in time. When the working face enters the lower part of 0251 goaf, the surrounding rock stress of the transport roadway decreases rapidly, and the prevention focus should be transferred from the transport roadway to the return air roadway. According to the results of numerical simulation, the impact zones can be divided and the prevention and control measures of impact zones in the mining were put forward. Field monitoring results show that the measures taken can effectively reduce the occurrence of rock burst.

Published
2023
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28. Duplex Mode Switching for Underlay Cognitive Radio Systems Based on Outage Probability

Author

Zhou, Ranran, Han, Liang, Li, Yupeng, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zhang, Junjie James, Series Editor, Wang, Wei, editor, Liu, Xin, editor, Na, Zhenyu, editor, Li, Xiaoxia, editor, and Zhang, Baoju, editor

Published
2021
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29. Optimization of Power Allocation for Full Duplex Relay-Assisted D2D Communication Underlaying Wireless Cellular Networks

Author

Zhou, Ranran, Han, Liang, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zhang, Junjie James, Series Editor, Wang, Wei, editor, Liu, Xin, editor, Na, Zhenyu, editor, Jia, Min, editor, and Zhang, Baoju, editor

Published
2020
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34. Development and experimental validation of an M2 macrophage and platelet‐associated gene signature to predict prognosis and immunotherapy sensitivity in bladder cancer

Author

Muhuitijiang, Bahaerguli, primary, Zhou, Jiawei, additional, Zhou, Ranran, additional, Zhang, Zhiyong, additional, Yan, Guang, additional, Zheng, Zaosong, additional, Zeng, Xiangbo, additional, Zhu, Yuanchao, additional, Wu, Haowei, additional, Gao, Ruxi, additional, Zhu, Tianhang, additional, Shi, Xiaojun, additional, and Tan, Wanlong, additional

Published
2024
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41. Paleo-vegetation and paleo-climate characteristics of Cretaceous and Paleogene strata in several typical basins in China: palynological evidence.

Author

Fu, Xiaoyan, Lu, Jungang, Chen, Shijia, Zhou, Ranran, Shi, Yulei, Zhao, Rongqian, and Yuan, Man

Subjects
PALEOGENE, DECIDUOUS plants, SALINE waters, COLD (Temperature), SALT lakes, WOODY plants
Abstract

The paleovegetation and paleoclimate characteristics are studied in the Palaeogene strata of Hetao Basin, Subei Basin and Qaidam Basin in China, and the Cretaceous Guyang Formation (K1g) in the Hetao Basin. These three basins receive high attention, different distribution areas, representative. Pollen evidence shows that: (1) The sporopollen assemblage of Palaeogene Linhe Formation (E3l) in Hetao Basin is characterised by Pinaceae-Ephedripites-Ulmipollenites-Chenopodipollis. It reflects that the ancient vegetation types were mainly coniferous and evergreen woody plants, and the climate was cold temperature. The sporopollen assemblage characteristics of the upper member of the Palaeogene Xiaganchaigou Formation (E32) in the Qaidam Basin are similar to it. (2) The sporopollen characteristics of the K1g in the Hetao Basin reflect that its ancient vegetation was dominated by evergreen woody plants and belongs to a warm and humid subtropical climate. (3) The assemblage of Palaeocene Funing Formation (E1f) in Subei Basin was Pterisisporites undulatus-Ulmipollenites minor-Taxodiaceaepollenites hiatus. The climate type was humid north temperate climate, vegetation was mainly deciduous trees and evergreen woody plants. (4) Leiosphaeridia/Granodiscus, Pediastrum and Botryococcus were also detected in the E1f of Subei Basin. The appearance of these algae indicates the special saline water environment and good hydrocarbon potential. [ABSTRACT FROM AUTHOR]

Published
2024
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46. Adaptive neural network observer control for a class of nonlinear strict-feedback systems with unmeasurable states.

Author

Zhou, Ranran, Wen, Guoxing, Zhu, Jiahao, and Li, Bin

Subjects
*NONLINEAR systems, *BACKSTEPPING control method, *ADAPTIVE control systems, *NONLINEAR equations, *STABILITY theory, *PSYCHOLOGICAL feedback
Abstract

This article addresses the backstepping control problem of the nonlinear strict-feedback system with an immeasurable state. To eliminate the effect coming from the immeasurable state variable, a new adaptive state observer method is developed for backstepping design by employing a neural network (NN) approximation strategy. As one of the highlighting contributions, the observer method can be performed with the relaxed condition because it does not require the design parameters to satisfy the Hurwitz equation, therefore it can be more easily applied and extended to serve for nonlinear system control than the existing observer methods. Finally, by integrating the observer dynamic into the backstepping design, the adaptive tracking control is achieved. Lastly, the feasibility of the method is proved by both stability theory and computer simulation. [ABSTRACT FROM AUTHOR]

Published
2024
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49. Optimized Backstepping Combined With Dynamic Surface Technique for Single-Input–Single-Output Nonlinear Strict-Feedback System

Author

Wen, Guoxing, Zhou, Ranran, Zhao, Yanlong, and Niu, Ben

Abstract

In this article, for the single-input–single-output (SISO) nonlinear strict-feedback system, optimized backstepping (OB) control combined with the dynamic surface (DS) technique is developed. OB is to make every subsystem control of backstepping as the optimized one so as to ensure the entire backstepping control being optimized. However, the original design of OB still needs to repeatedly calculate the derivative of virtual controls, as a result, it will inevitably cause the problem of “differential explosion.” In order to alleviate the phenomenon, the OB control is combined with the DS technique. Furthermore, OB control needs to conduct with reinforcement learning (RL) in every backstepping step, hence simplifying the algorithm of RL is very necessary and substantive for achieving the combination. In this work, because the optimized control derives both critic and actor training laws by utilizing a simple positive function instead of the square of approximation of Hamilton–Jacobi–Bellman (HJB) equation, it can obviously simplify the RL algorithm to compare with the traditional optimizing methods. Finally, the feasibility is illustrated via both theory and simulation.

Published
2024
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50. A 55-nm Three-Stage Operational Transconductance Amplifier With Single Cascode Miller Compensation for Large Capacitive Loads

Author

Zhou, Ranran, Wang, Haozhe, Wang, Peng, Poechmueller, Peter, and Wang, Yong

Abstract

With the scaling down of the transistor technology, intrinsic gains of the devices are continuously dropping. Meanwhile, high-gain operational transconductance amplifiers (OTAs) using technologies with reduced feature sizes are required in various applications. This article presents a 55-nm-fabricated three-stage OTA with a single cascode Miller capacitor for driving large capacitive loads. To achieve a high dc gain, a gain enhancement (GE) circuit is used in the first stage to boost the overall voltage gain to above 100 dB. To obtain a stable frequency response, a cascode Miller compensation scheme together with the GE circuits are used to push the nondominant complex pole to higher frequency and adjust the $Q$ -factor. The proposed three-stage OTA is implemented in a 55-nm low-power (LP) CMOS process and occupies an area of 0.005 mm2. A current consumption of $157 \mu \text{A}$ can be measured with a supply voltage of 1.2 V. The measured results show that this three-stage OTA can achieve stable frequency and transient step responses when driving 2.5-to-30-nF capacitive loads. With a 15-nF capacitive load, a gain bandwidth (GBW) of 0.82 MHz, a phase margin (PM) of 53°, an average slew rate of 0.13 V/ $\mu \text{s}$ , and an average 1% settling time of $2.62 \mu \text{s}$ can be achieved.

Published
2023
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