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Influence of backfilling rate on the stability of the"backfilling bodyimmediate roof"cooperative bearing structure

International Journal of Mining Science and Technology 2022年第6期32卷 1197-1206页

作者： Xianjie Du Guorui Feng Min Zhang Zehua Wang wenhao liu College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China Key Laboratory of Shanxi Province for Mine Rock Strata Control and Disaster Prevention Taiyuan 030024China State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China Zhengzhou Coal Industry(Group)Co LtdZhengzhou 450007China College of Civil Engineering Taiyuan University of TechnologyTaiyuan 030024China

To reduce the cost of backfilling coal mining and utilize the underground space of coal mines,a new backfilling mining method with low backfilling rate called constructional backfilling coal mining(CBCM)is *** "backfilling body-immediate roof" cooperative bearing structure of CBCM is analyzed by establishing the model of the medium thick plate on an elastic *** influence of the backfilling rate on the stability of overlying strata is analyzed by the numerical simulation *** control effect of CBCM is verified by a physic similar simulation *** economic benefit of CBCM is *** conclusions are:the deformation characteristics of the immediate roof and critical backfilling spacing in CBCM can be analyzed based on the Hu Haichang’s *** the bearing capacity of the immediate roof is beneficial to the stability of the overlying *** CBCM has a good control effect on the overburden in Xinyang Mine when the backfilling rate is lower than 25%.The backfilling cost of per ton coal is 37.39 yuan/t when the backfilling rate is 13.7%,with a decrease rate of 56.63%than the *** research results can provide theoretical support for the application of CBCM in coal mining.

关键词： Constructional backfilling coal mining Immediate roof Cooperative bearing structure Medium thick plate on elastic foundation Backfilling rate Overlying strata

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Sphalerite Rb-Sr Dating and in situ Sulfur Isotope Analysis of the Daliangzi Lead-Zinc Deposit in Sichuan Province, SW China

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Journal of Earth Science 2018年第3期29卷 573-586页

作者： wenhao liu Xiaojun Zhang Jun Zhang Manrong Jiang Faculty of Earth Resources China University of Geosciences Institute of Geological Survey China University of Geosciences

This study reports the sphalerite Rb-Sr age and LA-MC-ICP-MS in situ sulfur isotope analysis results of the Daliangzi Lead-Zinc Deposit in the Sichuan-Yunnan-Guizhou （SYG） triangle. Sphalerite Rb-Sr dating yields a Mississippian age of 345.2±3.6 Ma （MSWD=I.4）, which is older than the published Late Triassic mineralization ages （230-200 Ma） of some other deposits. This indicates that at least two stages of lead-zinc mineralization have occurred in the SYG lead-zinc triangle. The first stage occurred in the Mississippian under an extensional environment, while the second stage occurred in the Late Triassic under a compressional environment. In situ sulfur isotope analysis of sphalerite growth zoning presents relatively large δ^34S values of 11.3‰-15.2‰ with small variations. The large δ^34S values indicate a reduced sulfur source of thermochemical reduction of seawater sulfates. Abundant organic matter in the black fracture zone possibly supplied reductants for thermochemical sulfate reduction （TSR） at the mineralization site. The small variation of δ^34S values suggests a slow and stable TSR process that could prevent the sudden supersaturation of sphalerite in the fluid and the resulting of fast participation. This is consistent with the well-crystallized characteristic of the sphalerite of the Daliangzi Deposit.

关键词： sphalerite Rb-Sr in situ sulfur isotope thermochemical reduction Daliangzi Mississippi Valley-type.

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Analysis and Optimization on Partition-Based Caching and Delivery in Satellite-Terrestrial Edge Computing Networks

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China Communications 2023年第3期20卷 252-285页

作者： Peng Wang Xing Zhang Jiaxin Zhang Shuang Zheng wenhao liu Wireless Signal Processing and Network Laboratory Key Laboratory of Universal Wireless CommunicationMinistry of EducationSchool of Information and Communication EngineeringBeijing University of Posts and TelecommunicationsBeijing 100876China

As a viable component of 6G wireless communication architecture,satellite-terrestrial networks support efficient file delivery by leveraging the innate broadcast ability of satellite and the enhanced powerful file transmission approaches of multi-tier terrestrial *** the paper,we introduce edge computing technology into the satellite-terrestrial network and propose a partition-based cache and delivery strategy to make full use of the integrated resources and reducing the backhaul *** on the interference effect from varied nodes in different geographical distances,we derive the file successful transmission probability of the typical user and by utilizing the tool of stochastic *** the constraint of nodes cache space and file sets parameters,we propose a near-optimal partition-based cache and delivery strategy by optimizing the asymptotic successful transmission probability of the typical *** complex nonlinear programming problem is settled by jointly utilizing standard particle-based swarm optimization(PSO)method and greedy based multiple knapsack choice problem(MKCP)optimization *** results show that compared with the terrestrial only cache strategy,Ground Popular Strategy,Satellite Popular Strategy,and Independent and identically distributed popularity strategy,the performance of the proposed scheme improve by 30.5%,9.3%,12.5%and 13.7%.

关键词： edge computing satellite terrestrial net-works caching deployment stochastic geometry 6G networks

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Research on ultrasonic-based investigation of mechanical properties of ice

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Acta Oceanologica Sinica 2021年第10期40卷 97-105页

作者： Xiaomin Chang wenhao liu Guangyu Zuo Yinke Dou Yan Li College of Water Resources Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China

Arctic sea ice area and thickness have declined dramatically during the recent *** ice physical and mechanical properties become increasingly *** methods of studying ice mechanical parameters such as ice-coring cannot realize field test and long-term observation.A new principle of measuring mechanical properties of ice using ultrasonic was studied and an ultrasonic system was proposed to achieve automatic observation of ice mechanical parameters(Young’s modulus,shear modulus and bulk modulus).The ultrasonic system can measure the ultrasonic velocity through ice at different temperature,salinity and density of *** ambient temperature decreased from 0°C to-30°C,ultrasonic velocity and mechanical properties of ice increased,and vice *** shear modulus of the freshwater ice and sea ice varied from 2.098 GPa to 2.48 GPa and 2.927 GPa to 4.374 GPa,*** bulk modulus of freshwater ice remained between 3.074 GPa and4.566 GPa and the sea ice bulk modulus varied from 1.211 GPa to 3.089 *** freshwater ice Young’s modulus kept between 5.156 GPa and 6.264 GPa and sea ice Young’s modulus varied from 3.793 GPa to 7.492 *** results of ultrasonic measurement are consistent with previous studies and there is a consistent trend of mechanical modulus of ice between the process of ice temperature rising and ***,this ultrasonic method and the ultrasonic system will help to achieve the long-term observation of ice mechanical properties of ice and improve accuracy of sea ice models.

关键词： ice mechanical properties ultrasonic testing spectrum analysis

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Formation of present desert landscape surrounding Jilantai Salt Lake in northern China based on OSL dating

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Frontiers of Earth Science 2015年第3期9卷 497-508页

作者： Yuxin FAN Xiaolong CHEN wenhao liu Fu ZHANG Fan ZHANG School of Earth Sciences and Key Laboratory of Mineral Resources in Western China of Gansu Province Lanzhou University Lanzhou 730000 China MOE Key Laboratory of Western China's Environmental Systems Collaborative Innovation Center for Arid Environments and Climate Change Lanzhou University Lanzhou 730000 China

The Jilantai Salt Lake （JSL）, a lake of importance due to its salt production in China since the early Qing dynasty, is surrounded by sand dunes. Exploration of the development of these sand dunes will be helpful for identifying the forces underlying the desert landscape and for identifying a solution to protect the salt resources. Through field investigation, we found sand dunes overlying either lacustrine and bog deposits on the lake bed at a lower altitude or littoral sediments on the higher lakeshores. Optically Stimulated Luminescence （OSL） dating results indicate that sands started to accumulate around the JSL as early as the early Holocene （around 11 ka）, while the rapid development of sand dunes occurred within the latest 0.1 ka. By comparison with climatic documents and human activities in adjacent regions, the initiation of sand accumulation around the JSL as early as the early Holocene is considered to be the result of low effective moisture in the Jilantai area. However, the rapid development of the sand dunes in the vast area surrounding the JSL was likely initiated by the intensified human activities which occurred within the latest 0.1 ka under warm and dry climatic conditions.

关键词： aeolian sand accumulation Jilantai Salt Lake,OSL dating

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Transfer-based Approximate Dynamic Programmingfor Rolling Security-constrained Unit Commitment with Uncertainties

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Protection and Control of Modern Power Systems 2024年第5期9卷 42-53页

作者： Jianquan Zhu Kai Zeng Jiajun Chen Wenmeng Zhao wenhao liu Wenkai Zhu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China Electric Power Research Institute China Southern Power GridGuangzhou 510700China

This paper studies the rolling security-constrained unit commitment(RSCUC)problem with AC power flow and *** this NP-hard problem,it is modeled as a Markov decision process,which is then solved by a transfer-based approximate dynamic programming(TADP)algorithm proposed in this *** from traditional approximate dynamic programming(ADP)algorithms,TADP can obtain the commitment states of most units in advance through a decision transfer technique,thus reducing the action space of TADP ***,compared with traditional ADP algorithms,which require to determine the commitment state of each unit,TADP only needs determine the unit with the smallest on-state probability among all on-state units,thus further reducing the action *** proposed algorithm can also prevent the iter-ative update of value functions and the reliance on rolling forecast information,which makes more sense in the rolling decision-making process of ***,nu-merical simulations are carried out on a modified IEEE 39-bus system and a real 2778-bus system to demonstrate the effectiveness of the proposed algorithm.

关键词： Rolling security-constrained unit com-mitment approximate dynamic programming decision transfer probability-based decision priority criterion uncertainty

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Applications of intelligent computing in vehicular networks

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Journal of Intelligent and Connected Vehicles 2018年第2期1卷 66-76页

作者： Daxin Tian Weiqiang Gong wenhao liu Xuting Duan Yukai Zhu Chao liu Xin Li Beihang University BeijingChina Nanjing LES Information Technology Co. LtdNanjingChina Department of Computer Science and Technology Tsinghua UniversityBeijingChina

Purpose–This paper aims to introduce vehicular network platform,routing and broadcasting methods and vehicular positioning enhancement technology,which are three aspects of the applications of intelligent computing in vehicular *** this paper,the role of intelligent algorithm in theﬁeld of transportation and the vehicular networks can be ***/methodology/approach–In this paper,the authors introduce three different methods in three layers of vehicle networking,which are data cleaning based on machine learning,routing algorithm based on epidemic model and cooperative localization algorithm based on the connect ***–In Section 2,a novel classiﬁcation-based framework is proposed to efﬁciently assess the data quality and screen out the abnormal vehicles in *** Section 3,the authors canﬁnd when trafﬁc conditions varied from freeﬂow to congestion,the number of message copies increased dramatically and the reachability also *** error of vehicle positioning is reduced by 35.39%based on the CV-IMM-EKF in Section ***,it can be concluded that the intelligent computing in the vehicle network system is effective,and it will improve the development of the car networking ***/value–This paper reviews the research of intelligent algorithms in three related areas of vehicle *** theﬁeld of vehicle networking,these research results are conducive to promoting data processing and algorithm optimization,and it may lay the foundation for the new methods.

关键词： Intelligent computing Vehicular ad hoc networks

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基于改进APF-QRRT^(*)策略的移动机器人路径规划

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电光与控制 2025年第1期32卷 21-26,33页

作者：刘文浩余胜东吴鸿源胡文科李小鹏蔡博凡马金玉温州大学机电工程学院浙江温州325000 国科温州研究院(温州生物材料与工程研究所) 浙江温州325000 南京航空航天大学航空学院南京210000

针对Q-RRT^(*)算法在路径规划过程中无法兼顾可达性和安全性的问题,提出一种改进APF-QRRT^(*)(IAPF-QRRT^(*))路径规划策略。IAPF-QRRT^(*)策略通过Q-RRT^(*)算法获得一组连接起点到终点的离散关键路径点,较传统的快速搜索随机树(RRT^(... 详细信息

针对Q-RRT^(*)算法在路径规划过程中无法兼顾可达性和安全性的问题,提出一种改进APF-QRRT^(*)(IAPF-QRRT^(*))路径规划策略。IAPF-QRRT^(*)策略通过Q-RRT^(*)算法获得一组连接起点到终点的离散关键路径点,较传统的快速搜索随机树(RRT^(*))算法具备更好的初始解和更快的收敛速度。改进传统人工势场(APF)方法获得一种新的无势正交向量场,在一定条件下使整体排斥向量场与吸引向量场正交,并将其作用于关键路径点,从而提高路径的安全性。将IAPF-QRRT^(*)策略与其他算法比较,通过数值模拟实验证明了所提策略的有效性。

关键词：移动机器人路径规划人工势场法 Q-RRT^(*)算法安全性

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Discovery of a new nontoxic cuprate superconducting system Ga-Ba-Ca-Cu-O

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Science China(Physics,Mechanics & Astronomy) 2018年第9期61卷 82-85页

作者： Yue Zhang wenhao liu Jin Si Xiyu Zhu Chengping He Haonan Zhao Hai-Hu Wen Center for Superconducting Physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced Microstructures Nanjing University

Superconductivity is observed in a new nontoxic cuprate system Ga-Ba-Ca-Cu-O,with T_c=82 K for Ga Ba_2Ca_5Cu_6O_(14+δ)(Ga-1256)and T_c=116 K probably for Ga Ba_2Ca_3Cu_4O_(10+δ)(Ga-1234)or Ga Ba_2Ca_2Cu_3O_(8+δ)(Ga-1223),*** compounds are fabricated by solid state reaction method under high pressure and high *** are characterized by resistivity,magnetization and X-ray diffraction(XRD)*** temperature dependence of magnetization measured in both zero-field-cooled and field-cooled processes on one sample(S1)shows two superconducting transitions at about 82 K and113 *** estimated shielding fraction for the phase with T_cof 82 K is about 67%,while the fraction for another phase with T_(c )of 113 K is quite *** XRD Rietveld refinement for S1 indicates two main phases existing in the sample,Ga-1256 with fraction of about 58%and non-superconducting Ca_(0.85)Cu O_2with fraction of about 42%***,we can conclude the superconducting phase with transition temperature of 82 K is due to *** resistivity measurement also confirms the superconductivity for S1,and the resistivity reaches zero at about 82 *** temperature dependence of magnetization for another sample(S2)shows much higher superconducting shielding fraction for the phase with T_cof 116 K,which may be a promising prospective for the synthesis of Ga-1234 or Ga-1223 phase.

关键词： cuprates high pressure and high temperature superconductivity

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Surficial modification enabling planar Al growth toward dendrite-free metal anodes for rechargeable aluminum batteries

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Science China Chemistry 2024年第4期67卷 1341-1351页

作者： wenhao liu Yu Li Bo Long Haoyi Yang Lumin Zheng Ying Bai Feng Wu Chuan Wu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019China

Al metal possesses ultrahigh theoretical volumetric capacity of 8,040 m Ah cm^(-3),and gravimetric capacity of 2,980 m Ah g^(-1),and thus is highly attractive for electrochemical energy ***,it suffers from several issues,such as the dendrite formation,during Al stripping-deposition cycling,which has been verified to account for the short circuit and limited cyclic ***,we use a facile and applicable method to in-situ reconstruct the Al anode surface with F-Al-O chemical bonds,which could preferentially induce the planar growth of Al along the interface plane,thus leading to the dendrite-free morphology evolution during the *** from F-Al-O chemical bonds on the surface of Al anodes,long lifespan of symmetric cells can be realized even under 1 m A cm^(-2)and 1 m Ah cm^(-2).Coupling the F-Al anode with graphite-based cathodes,high-voltage dual-ion Al metal batteries can be achieved with long-term cycle stability up to 1,200 cycles(at 0.5 m A cm^(-2)),surpassing the counterparts using pristine Al metal ***,the effectiveness of this surficial modification strategy is also elucidated with the aid of theoretical *** work provides novel insights on low-cost and facile strategies against the Al dendrite growth in aluminum batteries.

关键词： rechargeable aluminum batteries Al metal anode Al dendrite dual-ion batteries surficial modification

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