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Improved Double Deep Q Network-Based Task Scheduling Algorithm in Edge Computing for Makespan Optimization

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Tsinghua Science and Technology 2024年第3期29卷 806-817页

作者： Lei zeng Qi liu Shigen Shen Xiaodong liu School of Computer Science Nanjing University of Information Science and TechnologyNanjing 210044China School of Software Nanjing University of Information Science and TechnologyNanjing 210044China School of Information Engineering Huzhou UniversityHuzhou 313000China School of Computing Edinburgh Napier UniversityEdinburghEH105DTUK

Edge computing nodes undertake an increasing number of tasks with the rise of business ***,how to efficiently allocate large-scale and dynamic workloads to edge computing resources has become a critical *** study proposes an edge task scheduling approach based on an improved Double Deep Q Network(DQN),which is adopted to separate the calculations of target Q values and the selection of the action in two networks.A new reward function is designed,and a control unit is added to the experience replay unit of the *** management of experience data are also modified to fully utilize its value and improve learning *** learning agents usually learn from an ignorant state,which is *** such,this study proposes a novel particle swarm optimization algorithm with an improved fitness function,which can generate optimal solutions for task *** optimized solutions are provided for the agent to pre-train network parameters to obtain a better cognition *** proposed algorithm is compared with six other methods in simulation *** show that the proposed algorithm outperforms other benchmark methods regarding makespan.

关键词： edge computing task scheduling reinforcement learning makespan Double Deep Q Network(DQN)

Geology and Geochemistry of the Bianbianshan Au-Ag-Cu-Pb-Zn Deposit, Southern Da Hinggan Mountains, Northeastern China

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Acta Geologica Sinica(English Edition) 2012年第3期86卷 630-639页

作者： zeng Qingdong liu Jianming liu Hongtao Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Bianbianshan deposit, the unique gold-polymetal （Au-Ag-Cu-Pb-Zn） veined deposit of the polymetal metallogenic belt of the southern segment of Da Hinggan Mountains mineral province, is located at the southern part of the Hercynian fold belt of the south segment of Da Hinggan Mountains mineral province, NE China. Ores at the Bianbianshan deposit occur within Cretaceous andesite and rhyolite in the form of gold-bearing quartz veins and veinlet groups containing native gold, electrum, pyrite, chalcopyrite, galena and sphalerite. The deposit is hosted by structurally controlled faults associated with intense hydrothermal alteration. The typical alteration assemblage is sericite ＋ chlorite ＋ calcite ＋ quartz, with an inner pyrite-sericite-quartz zone and an outer seicite - chlorite - calcite-epidote zone between orebodies and wall rocks. δ34 S values of 17 sulfides from ores changing from -1.67 to ＋0.49‰ with average of -0.49‰, are similar to δ34 S values of magmatic or igneous sulfide sulfur. 206Pb/204Pb, 207Pb/204Pb and 208Pb/ 204Pb data of sulfide from ores range within 17.66-17.75, 15.50-15.60, and 37.64-38.00, respectively. These sulfur and lead isotope compositions imply that ore-forming materials might mainly originate from deep sources. H and O isotope study of quartz from ore-bearing veins indicate a mixed source of deep-seated magmatic water and shallower meteoric water. The ore formations resulted from a combination of hydrothermal fluid mixing and a structural setting favoring gold-polymetal deposition. Fluid mixing was possibly the key factor resulting in Au-Ag-Cu-Pb-Zn deposition in the deposit. The metallogenesis of the Bianbianshan deposit may have a relationship with the Cretaceous volcanic-subvolcanic magmatic activity, and formed during the late stage of the crust thinning of North China.

关键词： Gold-polymetal deposit isotopes Da Hinggan Mountains China

Genetic algorithm for autonomic joint radio resource management in end-to-end reconfigurable systems

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 11-17页

作者： zeng xian MA Tao LIN Yue-wei FENG Zhi-yong Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry of Education Beijing 100876 China

This article presents the genetic algorithm （GA） as an autonomic approach for the joint radio resource management （JRRM） amongst heterogeneous radio access technologies （RATs） in the end-to-end reconfigurable systems. The joint session admission control （JOSAC） and the bandwidth allocation are combined as a specific decision made by the operations of the genetic algorithm with certain advisable modifications. The proposed algorithm is triggered on the following two conditions When a session is initiated, it is triggered for the session to camp on the most appropriate RAT and select the most suitable bandwidth for the desired service. When a session terminates, it is also used to adjust the distribution of the ongoing sessions through the handovers. This will increase the adjustment frequency of the JRRM controller for the best system performance. Simulation results indicate that the proposed autonomic JRRM scheme not only effectively reduces the handover times, but also achieves well trade-off between the spectrum utility and the blocking probability.

关键词： genetic algorithm handover heterogeneous network,joint radio resource management reconfigurability

China’s carbon accounting system in the context of carbon neutrality: Current situation, challenges and suggestions

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Advances in Climate Change Research 2023年第1期14卷 23-31页

作者： Hong-Shuo YAN xian-Chun TAN An zeng Ling-Si KONG Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China School of Public Policy and Management University of Chinese Academy of SciencesBeijing 100049China Center for Carbon Neutrality Strategy Institutes of Science and DevelopmentChinese Academy of SciencesBeijing 100190China

Global climate governance is currently at the stage of carbon *** the quality of emissions inventories at different levels has become a critical climate governance task,which not only contributes to the Global Stocktake but also helps verify compliance progress and address new trade *** study provides a comprehensive review of international carbon accounting standards and guidelines while assessing the potential impact of upcoming carbon tax policies,such as the EU CBAM and the *** this basis,the current situation and challenges of China's carbon emission accounting system are systematically analysed,and suggestions for improvement are *** results show that carbon tax policies will increase the requirements for emission inventories and will strengthen the correlation between different *** improvement of China's carbon accounting system should be *** the regional carbon accounting guidelines are already in line with international guidelines,further improvements are needed at the enterprise and product *** boundaries need to be set in China's corporate carbon accounting guidelines,and the speed of developing product carbon accounting guidelines should be *** quality of emissions inventories should be comprehensively improved by implementing a combination of policies,including corporate carbon information disclosure,green supply chain construction,activity data statistics and verification,and a dynamic emission factor database.

关键词： Carbon neutrality Carbon emission Policy suggestion Accounting

ANALYSIS ON THERMAL ELASTO-PLASTIC ASPERITY CONTACTS OF LAYERED MEDIA

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Chinese Journal of Mechanical Engineering 2008年第2期21卷 5-12页

作者： TONG Ruiting liu Geng zeng Quanren liu Tianxiang School of Mechatronic Engineering Northwestern Polytechnical University Xi＇an 710072 China

A thermal elasto-plastic asperity contact model is investigated, which takes into account the steady-state heat transfer and the asperity distortion due to thermal elasto-plastic deformations. A hard coating and a soft coating are applied to study the correlations between contact area and contact pressure, average gap and contact pressure, coating thickness and contours of the contact stress distribution, etc. The effects of material properties, coating thickness, frictional coefficient, and the heat input combinations on the stress distribution are investigated and discussed. The frictional heat input increases the maximum value of yon Mises stress. Finally, the appropriate thickness of the hard coating is also discussed. To protect the substrate, one can choose hard coating and the thickness of that is suggested that can be hc=70 Rm.

关键词： Thermal elasto-plastic contact Rough surfaces Coating

Electron emission induced by keV protons from tungsten surface at different temperatures

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Chinese Physics B 2022年第7期31卷 241-246页

作者： Li-Xia zeng xian-Ming Zhou Rui Cheng Yu liu Xiao-An Zhang Zhong-Feng Xu Ion Beam and Optical Physical Laboratory Xianyang Normal UniversityXianyang 712000China Institute of Science and Technology for Laser and Particle Beams Xi’an Jiaotong UniversityXi’an 710049China Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China

The electron emission yield is measured from the tungsten surface bombarded by the protons in an energy range of 50keV–250keV at different *** our experimental results,the total electron emission yield,which contains mainly the kinetic electron emission yield,has a very similar change trend to the electronic stopping *** the same time,it is found that the ratio of total electron emission yield to electronic stopping power becomes smaller as the incident ion energy *** experimental result is explained by the ionization competition mechanism between electrons in different shells of the target *** explanation is verified by the opposite trends to the incident energy between the ionization cross section of M and outer shells.

关键词： electron emission x-ray electronic stopping power work function

Urban development and resource endowments shape natural resource utilization efficiency in Chinese cities

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Journal of Environmental Sciences 2023年第4期126卷 806-816页

作者： Yanbing liu Fei Lu Chaofan xian Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, we established a comprehensive natural resource utilization efficiency index(NRUEI). We then calculated the 2016 index for 165 cities in China,and investigated what caused it to vary. We found three main results:(1) the NRUEI varied greatly across China and there were significant positive correlations between urban energy utilization efficiency(EUE), water utilization efficiency(WUE) and land utilization efficiency(LUE);(2) the NRUEI showed a significant positive correlation with a city’s population size,economy(Gross Domestic Product(GDP)), and the level of urban social development(GDP per capita);(3) cities in East China have the highest natural resource utilization efficiency,while cities in Northeast China have the lowest. These results indicate that China’s increasing urban development is associated with rising natural resource utilization efficiency and that the city’s endowment of natural resources is an important factor affecting that efficiency. Further, the results showed that the determinants of a city’s NRUEI differed in large and small cities. Lastly, our results suggest that improving EUE is key for improving NRUEI in urban China, and different efficiencies can be improved intertwined. A major takeaway of this study is that there is great potential for improving natural resource utilization efficiency in Chinese cities and we include city-specific suggestions for efficiency improvements.

关键词： Urban development Resource endowment Resource utilization efficiency Sustainable city

Effects of Cooling Rate and Component on the Microstructure and Mechanical Properties of Mg–Zn–Y Alloys

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 7-14页

作者： Shuang Shao Yong liu Chun-Shui Xu Ying-Xuan Xu Bin Wu Xiao-Shu zeng xian-Feng Lu xiang-Jie Yang Key Laboratory of Near Net Forming of Jiangxi Province Nanchang University

The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates（Rc） from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0：45：45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction（Vf） of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.

关键词： Mg–Zn–Y alloys Microstructural characterization Compressive strength Cooling rate Interdependence theory

Text Detection in Natural Scene Images Using Morphological Component Analysis and Laplacian Dictionary

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 214-222页

作者： Shuping liu Yantuan xian Huafeng Li Zhengtao Yu School of Information Engineering and Automation and Key Laboratory of Intelligent Information Processing Kunming University of Science and Technology

Text in natural scene images usually carries abundant semantic information. However, due to variations of text and complexity of background, detecting text in scene images becomes a critical and challenging task. In this paper, we present a novel method to detect text from scene images. Firstly, we decompose scene images into background and text components using morphological component analysis(MCA), which will reduce the adverse effects of complex backgrounds on the detection *** order to improve the performance of image decomposition,two discriminative dictionaries of background and text are learned from the training samples. Moreover, Laplacian sparse regularization is introduced into our proposed dictionary learning method which improves discrimination of dictionary. Based on the text dictionary and the sparse-representation coefficients of text, we can construct the text component. After that, the text in the query image can be detected by applying certain heuristic rules. The results of experiments show the effectiveness of the proposed method.

关键词： Dictionary learning Laplacian sparse regularization morphological component analysis(MCA) sparse representation text detection