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A Back-to-back VSC-HVDC System of Yu-E Power Transmission Lines to Improve Cross-region Capacity

CSEE Journal of Power and Energy Systems 2020年第1期6卷 64-71页

作者： Yinbiao Shu Guangfu Tang Hui Pang China Huaneng group Co. Ltd.Xicheng DistrictBeijing 100031China Global Energy Interconnection Research Institute Co. Ltd.Changping DistrictBeijing 102209China

With the rapid development of hydropower in the southwest of China, the energy transmitted by ultra high volt- age direct current (UHVDC) is ever increasing. At the same time, the power grid continues to expand westward, creating a service area. The stability of the Southwest China Power Grid is becoming a major issue. It is necessary to coordinate the development of hydropower and the construction of cross-region interconnections to optimize the grid structure. The Yu-E denotes the connection between the two region Yu (Chongqing) and E (Hubei) in China. The Yu-E project is a back-to-back voltage source converter based high voltage direct current (VSC-HVDC) project designed to realize an asynchronous connection of the Southwest and Central China Power Grids. The project will improve the bi-directional power support capability and optimize the grid structure. In addition, the Yu-E project will improve hydropower cross-region transmission capacity and enable the Southwest China Power Grid to utilize the power from the Three Gorges in the Central China Power Grid. In this paper, the fault isolation, low-frequency oscillation, sub-synchronous oscillation and short-circuit level are investigated and analyzed. Meanwhile, the impact of the Yu-E project on AC systems is studied in detail. In the end, the overall system design of the Yu-E project is introduced. The research results show that the Yu-E project can increase the transmission capability of the Southwest and Central China Power Grids, and enhance the stability of asynchronously interconnected AC systems. At the same time, the Yu-E project also serves as a demonstration project for the future development and application of VSC technology for the world.

关键词： Additional control asynchronous interconnec-tion back-to-back system design VSC-HVDC

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Optimization and Design of Cloud-Edge-End Collaboration Computing for Autonomous Robot Control Using 5G and Beyond

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Journal of Beijing Institute of Technology 2022年第5期31卷 454-463页

作者： Hao Wang China Railway Siyuan Survey and Design group Co. Ltd.Wuhan 430063China

Robots have important applications in industrial production, transportation, environmental monitoring and other fields, and multi-robot collaboration is a research hotspot in recent years. Multi-robot autonomous collaborative tasks are limited by communication, and there are problems such as poor resource allocation balance, slow response of the system to dynamic changes in the environment, and limited collaborative operation capabilities. The combination of 5G and beyond communication and edge computing can effectively reduce the transmission delay of task offloading and improve task processing efficiency. First, this paper designs a robot autonomous collaborative computing architecture based on 5G and beyond and mobile edge computing(MEC).Then, the robot cooperative computing optimization problem is studied according to the task characteristics of the robot swarm. Then, a reinforcement learning task offloading scheme based on Qlearning is further proposed, so that the overall energy consumption and delay of the robot cluster can be minimized. Finally, simulation experiments demonstrate that the method has significant performance advantages.

关键词： robot collaboration mobile edge computing(MEC) 5G and beyond network task offloading resource allocation

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AlScN films prepared by alloy targets and SAW device characteristics

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Journal of Rare Earths 2023年第3期41卷 434-439,I0004页

作者： Kuo Men Hao Liu Xingquan Wang Qian Jia Zhaochong Ding Huating Wu Daogao Wu Yuhua Xiong State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing 100088China GRIMAT Engineering Institute Co. Ltd.Beijing 101402China State Key Laboratory of Non-ferrous Metals and Processes GRINM Group Co.Ltd.Beijing 100088China GRIKIN Advanced Material Co.ltd. Beijing 100220China GRIREM Advanced Materials Co.ltd. Beijing 100088China

In this paper,we reported a surface acoustic wave(SAW)device prepared and optimized by piezoelectric films containing AIN,AIScN(Sc-20 at%)and AIScN(Sc-30 at%)by reactive magnetron sputtering using Al and AISc alloy *** calculated the material intrinsic electromechanical coupling coefficient k_(t)^(2) of AlScN(Sc-20 at%)and AlScN(Sc-30 at%)which are much better than *** can be explained by the lattice ***,the results were confirmed by transmission electron microscopy(TEM)observation of the *** the SAW devices based on three thin films were tested by vector network analysis obtaining the device equivalent electro mechanical coupling coefficient k_(eff)^(2).The value of AIScN(Sc-20 at%)k_(eff)^(2),which equals to 1.94%,is higher than that of AIN and AIScN(Sc-30 at%)while the value of AIScN(Sc-30 at%)k_(t)^(2) is higher than that of *** is shown in our study that the crystallinity and orientation of the material still have a greater impact on k_(eff)^(2) but it does not have influence on k_(t)^(2) in the actual device preparation process.

关键词： AlScN film Alloy targets SAW Electromechanical coupling coefficient k_(t)^(2) Crystallinity Orientation

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Viscous properties of new mould flux based on aluminate system with CeO_2 for continuous casting of RE alloyed heat resistant steel

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Journal of Rare Earths 2016年第3期34卷 328-335页

作者：亓捷刘承军李春龙姜茂发 Key Laboratory for Ecological Metallurgy of Multimetallic Ores (Ministry of Education) Northeastern University Baotou Iron and Steel (group) Co. Ltd.

The conventional mould fluxes can not be applied to the continuous casting of RE alloyed heat resistant steel, because severe slag-metal interface reactions occur generally in the mold. To restrain the interface reaction and improve conditions for continuous casting, a new mould flux based on aluminate system was devised. The viscous properties were investigated. Scanning electron microscopy and X-ray diffraction were applied to detect and characterize the crystalline phases in the continuous cooling process. The results showed that appropriate addition of CeOcould avoid the precipitation of CaO and decrease the viscosity of the mould flux. Increasing the mass ratio of CaO /AlO, especially to a value exceeding 1, could worsen the stability of the mould flux. With a content of less than 14 wt.%, LiO could reduce the viscosity and breaking temperature, but its effect could be weakened for the promoted precipitation of LiAlO. To obtain a mould flux with stable viscous properties, such as viscosity and breaking temperature, appropriate contents of CeOand LiO should be controlled to around 10 wt.% and 14 wt.%, while the mass ratio of CaO /AlOshould not be more than 1.

关键词： mould flux aluminate melt viscosity rare earth steel heat resistant steel

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Smart OLT equipment of optical access network

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Optoelectronics Letters 2023年第3期19卷 159-163页

作者： TANG Zhifei GAO Junshi YANG Tianpu LIU Dongmei DAI Guangchong China Mobile group Design Institute Co. Ltd.Beijing 100080China

A distributed architecture of optical line terminal(OLT)equipment is proposed for response to national bandwidth acceleration requirements and for future smooth evolution to 50G passive optical network(PON).This architecture moves the forwarding function of the control board to each service board to improve the switching capacity and performance of the *** traditional control boards of centralized architecture OLT equipment have exchange and traffic processing function,and every service board is only controlled by the control *** the distributed architecture of OLT equipment,control boards still maintain exchange function,whereas service boards have traffic processing *** method separates the exchange and traffic processing functions,which improves *** paper also presents optical access network equipment combined with telemetry technology that provides reliable guarantee for intelligent analysis and data *** with the traditional push mode of network management,the data collected by network management combined with telemetry technology and artificial intelligence(AI)analysis can be used for network planning,assurance of the bandwidth and accurate operation.

关键词： network OLT Smart

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Recovery of iron from lead-zinc metallurgical slags by bath smelting

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Journal of Central South University 2015年第4期22卷 1256-1263页

作者：刘群王重庆谭军尹周澜陈启元廖舟张平民刘洋 Key Laboratory of Resources Chemistry of Nonferrous Metals of Ministry of Education (Central South University) Zhuzhou Smelter group Co. Ltd.

The recovery of iron from iron sinking slag and lead smelter slag was investigated by desulfurization-reduction bath smelting. The effects of lead smelter slag(LSS) to iron sinking slag(ISS) mass ratio and temperature were investigated in desulfurization experiments. The X-ray diffraction(XRD) and X-ray fluorescence(XRF) analyses show that the optimum conditions are LSS:ISS of 3:7 and temperature of 1350°C. The composition of desulfurization products is mainly Zn Fe2O4, and the desulfurization rate of 99.66% is obtained under optimum conditions. The thermogravimetric(TG) and differential scanning calorimeter(DSC) analyses demonstrate that reductant is necessary for decomposition and reduction of zinc ferrite in desulfurization product. The effects of reductant, temperature and feeding modes on iron enrichment were investigated in reduction experiments. The scanning electron microscope(SEM) and energy dispersive spectrometer(EDS) determination show that the iron content of reduction product is up to 99.36% under optimum conditions of coke as reductant, reduction temperature of 1450°C and the feeding mode of premixing.

关键词： lead smelter slag iron sinking slag desulfurization reduction thermal analysis

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Removal of chloride from simulated acidic wastewater in the zinc production

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Chinese Journal of Chemical Engineering 2019年第5期27卷 1037-1043页

作者： Weizao Liu Li Lu Yao Lu Xiaowei Hu Bin Liang College of Chemical Engineering Sichuan UniversityChengdu 610065China China Tin group Co. Ltd.Liuzhou 545000China

The removal of chloride from the zinc electrolyte produced during hydrometallurgical zinc production is challenging. The ion-exchange method is a promising way to remove chloride if the resin washing wastewater can be recycled. This paper focuses on chloride removal from resin washing wastewater to enable its reuse. Various processing factors including the oxygen gas velocity, temperature, and reaction time were investigated systematically. The results show that the optimal conditions for dechlorination are an oxygen gas velocity of 0.5 L-min^-1, a reaction temperature of 80 ℃, and a reaction time of 30 min. A dechlorination efficiency of 80% with a residual chloride ion concentration less than 200 mg-L^-1 was achieved, which meets the requirements for the recycling of wastewater. The presence of manganese accelerates the dechlorination by forming a Mn^2+- MnO^2-MnO4^-Mn^2+ redox cycle. In this process, about 15 kg of the MnO2 and all of the zinc can be recovered from 100 m^3 wastewater, and the wastewater can be reused, which makes the ion-exchange method a promising technique for chloride removal.

关键词： Ion-exchange Dechlorination Ozone Zinc production Oxidation

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Mechanical properties of frozen rock mass with two diagonal intersected fractures

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International Journal of Mining Science and Technology 2018年第4期28卷 626-633页

作者： Hao Yang Renliang Shan Jinxun Zhang Fumei Wu Zhiming Guo School of Mechanics and Civil Engineering China University of Mining & Technology Postdoctoral Workstation Beijing Urban Construction Group CO. Ltd.

Based on previous research results, this paper investigated the influence of fracture morphology on mechanical properties and failure modes of rock mass with two diagonal intersected fractures. This study carried out a series of triaxial compression tests on rock-like specimens with two crossed fractures under negative temperature, concluded the following conclusions. The strength and failure modes of rock mass are significantly influenced by the dips of two crossed fractures. The strength of rock mass with two frac- tures cannot simply be estimated using the method that was developed for the rock mass with a single fracture. When the intersecting angle is less than 30~, the failure plane initiates at the tip of ＂artificial rup- tures＂ and extends to the upper and lower ends of the specimen. In case of a higher dip and intersecting angle ranging from 30° to 60°, the failure plane propagates along one of these two fractures. The mechan- lca! parameters of rock mass are not only related to the trace length, but also depend on the trace !ength ratio. One could roughly calculate the strength parameters using the approximation proposed *** paper..For the rock mass with a trace length ratio 〈0.3 （short trace length/long trace length）, the failure mode is dependent on the fracture with a longer trace length. When the trace length becomes significant and the trace length ratio approximates to 1, the failure plane propagates along two fractures, where an *** pattern is presented： For the rock mass with moderate frac!ures and a trace length ratio of approxlmately 1, the failure mode *** on fractures, which is simllar to .the damage pattern of intact rock. The strength, and elastic .modulus of rock mass decrease with the increase of spacing between fractures, whl!e Polsson＇s ratio is Independent on the spacing. The failure mode can be deter- mined by the area. of triangle created by two fractures. Damage occurs at the smaller triangle area first, an

关键词： Intersected fractures Fracture morphology Failure modes Mechanical properties

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An energy minimization algorithm based on distributed dynamic clustering for long term evolution(LTE) heterogeneous networks

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Science China(Information Sciences) 2015年第4期58卷 103-114页

作者： TONG En DING Fei PAN ZhiWen YOU Xiao Hu National Mobile Communications Research Laboratory Southeast University Research and Development Center China Mobile Group Jiangsu Co. Ltd.

Energy saving has become an important issue in wireless communications from both environment and economic considerations. In this paper, an energy minimization algorithm based on distributed dynamic clustering(DDCEM) with lower complexity, higher performance, and better adaptability for heterogeneous network(Het Net) is proposed. A Het Net could be divided into several clusters, which is defined as one group of a network node and users served by the node. A energy efficient user association, which dynamically changes according to real-time energy efficiency(EE) evaluation with traffic load and location distribution of each cluster, can be employed to save consumed energy. Then, the optimal sleeping relay is found as follows. First,the sleeping probability cost of each relay station(RS) is computed and ranked based on the user traffic and the position distribution of each cluster, and the relay with minimum sleeping probability is selected to be switched off. Hence, the sleep node is selected taking into account the traffic load and location of the Evolved Node B(e NB) and all the RSs. The complexity of the algorithm is greatly reduced because the user association operation and network load evaluation are fulfilled cluster by cluster. Simulation results show that the proposed DDCEM strategy offers EE gain with low system complexity.

关键词： energy efficiency heterogeneous network traffic cluster sleeping probability cost

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Preparation of pure SbCl_3 from lead anode slime bearing high antimony and low silver

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Transactions of Nonferrous Metals Society of China 2010年第12期20卷 2397-2403页

作者：曹华珍陈进中袁海军郑国渠 College of Chemical Engineering and Materials Zhejiang University of Technology Department of Science and Technology Guangxi China Tin Group Co.Ltd.

A novel treatment process of lead anode slime bearing high antimony and low silver was developed by a potential-controlled chloridization leaching and continuous *** experimental results show a high Sb 3+ concentration,489.2 g/L,in the leaching solution for two-stage countercurrent leaching process,and the leaching rates of Sb,Cu,Bi more than 99% when the potential is controlled at 450 *** the leaching solution is distillated and concentrated at 120°C,almost all the silicon compound is evaporated into the concentration distillate and exists as amorphous hydrated *** the continuous distillation,high pure SbCl3 could be prepared,and AsCl3 is enriched in the distillate while metals Bi,Cu are enriched in the continuous distillation *** a result,the recovery rate of Sb is more than 95%.

关键词： lead anode slime potential-controlled chloridization leaching continuous distillation antimony trichloride

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