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Identifying influential nodes in social networks via community structure and influence distribution difference

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Digital Communications and Networks 2021年第1期7卷 131-139页

作者： Zufan Zhang Xieliang Li Chenquan gan School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China Chongqing Key Laboratory of Mobile Communications Technology Chongqing400065China Engineering Research Center of Mobile Communications Ministry of EducationChongqing400065China

This paper aims to effectively solve the problem of the influence maximization in social *** this purpose,an influence maximization method that can identify influential nodes via the community structure and the influence distribution difference is ***,the network embedding-based community detection approach is developed,by which the social network is divided into several high-quality ***,the solution of influence maximization is composed of the candidate stage and the greedy *** candidate stage is to select candidate nodes from the interior and the boundary of each community using a heuristic algorithm,and the greedy stage is to determine seed nodes with the largest marginal influence increment from the candidate set through the sub-modular property-based Greedy ***,experimental results demonstrate the superiority of the proposed method compared with existing methods,from which one can further find that our work can achieve a good tradeoff between the influence spread and the running time.

关键词： Social network Community detection Influence maximization Network embedding Influence distribution difference

Strong cosmic censorshiP for a scalar field in a logarithmic-de Sitter black hole

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Communications in Theoretical Physics 2020年第3期72卷 60-68页

作者： Yiqian Chen Qingyu gan Guangzhou Guo Center for Theoretical Physics College of PhysicsSichuan UniversityChengdu610064China

It has been shown that the quasinormal modes of perturebated fields can be used to investigate the validity of strong cosmic censorship(SCC).Relevant issues for Reissner-Nordstrom-de Sitter(RN-dS)black holes and Born-Infeld-de Sitter black holes have been *** this paper,we investigate SCC in an asymptotic RN-dS black hole with logarithmic nonlinear electromagnetic field perturbed by massless scalar *** has been argued that SCC can be violated in a near-extremal RN-dS black ***,we find that the NLED effect can rescue SCC for a near-extremal logarithmic-de Sitter black *** with Born-Infeld model,we find that the NLED effect has similar behavior.

关键词： logarithmic electrodynamics quasinormal mode strong cosmic censorship

On the density of Birkhoff sums for Anosov diffeomorphisms

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Science China Mathematics 2022年第2期65卷 319-330页

作者： Shaobo gan Yi Shi Mingyang Xia School of Mathematical Sciences Peking UniversityBeijing 100871China

Let f : M → M be an Anosov diffeomorphism on a nilmanifold. We consider Birkhoff sums for a Holder continuous observation along periodic orbits. We show that if there are two Birkhoff sums distributed at both sides o... 详细信息

关键词： Anosov diffeomorphism Birkhoff sum periodic point nilmanifold

Surface reconstruction with spherical harmonics and its application for single particle crushing simulations

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 232-239页

作者： Deheng Wei Budi Zhao Yixiang gan School of Civil Engineering The University of SydneySydneyNSW2006Australia School of Civil Engineering University College DublinDublinIreland

Particle morphology has great influence on mechanical behaviour and hydro/thermal/electrical conductivities of granular *** reconstruction and mesh generation are critical to consider realistic particle shapes in various computational *** study adopts the combined finitediscrete element method(FDEM)to investigate single particle crushing *** shapes were reconstructed with spherical harmonic(SH)in both spherical and Cartesian coordinate ***,the reconstructed surface mesh qualities in two coordinate systems are investigated and *** the efficiency of the two SH systems in reconstructing star-like shapes is nearly identical,SH in Cartesian coordinate system can reconstruct non-star-like shapes with the help of surface ***,a higher triangular mesh quality is generated with spherical *** single particle crushing tests,the low mesh quality produces more fluctuations on load-displacement *** particles with more surficial mesh elements tend to have a lower contact stiffness due to more contact stress concentrations induced by complexity of morphology features and more volumetric tetrahedral *** fracture patterns are also influenced by mesh quality and density,e.g.a particle with fewer mesh elements has a simpler fragmentation *** study serves as an essential step towards modelling particle breakage using FDEM with surface mesh directly from SH reconstruction.

关键词： Numerical modelling Particle morphology Particle crushing/crushability Particle-scale behaviour Sands

Data-driven optimal switching and control of switched systems

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Control Theory and Technology 2021年第3期19卷 299-314页

作者： Chi Zhang Minggang gan Chenchen Xue School of Automation Beijing Institute of TechnologyBeijing100081China Beijing Institute of Control Engineering BeijingChina China Academy of Launch Vehicle Technology BeijingChina

In this paper,optimal switching and control approaches are investigated for switched systems with infinite-horizon cost functions and unknown continuous-time *** first,for switched systems with autonomous subsystems,the optimal solution based on the finite-horizon HJB equation is proposed and a data-driven optimal switching algorithm is ***,for the switched systems with subsystem inputs,a data-driven optimal control approach based on the finite-horizon HJB equation is *** data-driven approaches approximate the optimal solutions online by means of the system state data instead of the subsystem ***,the convergence of the two approaches is ***,the validity of the two approaches is demonstrated by simulation examples.

关键词： Switched systems Optimal switching Optimal control Data-driven control

Slicing-response model for ablation mass removal of polyformaldehyde irradiated by pulsed CO_2 laser in vacuum

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Science China(Technological Sciences) 2015年第1期58卷 158-162页

作者： LI gan CHENG MouSen LI XiaoKang National University of Defense Technology College of Aerospace Science and Engineering

The interaction between CO2 laser and polyformaldehyde(POM)is quite important in the research of laser irradiation effects and *** this time,the accuracy of the existing mass-ablation models for POM irradiated by CO2 laser is poor compared with the experimental *** on the energy distribution deposited in the POM target,the active area excited by laser is divided into four slices,the ablation slice(the temperature-rising slice,the perturbation slice,and the undisturbed slice),and a slicing response model for the mass ablation of POM induced by pulsed CO2 laser irradiation in vacuum is developed.A formula is deduced to predict the ablated mass areal density from the model and is verified with data from several studies and our own *** results show that our model fits the experimental data quite well before the shielding effect of ablation products becomes *** applicability of the model to other materials and the mass ablation in atmosphere are also briefly explored.

关键词： laser ablation pulsed CO2 laser polyformaldehyde(POM) ablation model

Cystine transporter SLC7A11/xCT in cancer:ferroptosis,nutrient dependency,and cancer therapy

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Protein & Cell 2021年第8期12卷 599-620页

作者： Pranavi Koppula Li Zhuang Boyi gan Department of Experimental Radiation Oncology The University of Texas MD Anderson Cancer CenterHoustonTXUSA The University of Texas MD Anderson UTHealth Graduate School of Biomedical Sciences HoustonTXUSA

The cystine/glutamate antiporter SLC7A11(also commonly known as xCT)functions to import cystine for glutathione biosynthesis and antioxidant defense and is overexpressed in multiple human *** studies revealed that SLC7A11 overexpression promotes tumor growth partly through suppressing ferroptosis,a form of regulated cell death induced by excessive lipid ***,cancer cells with high expression of SLC7A11(SLC7A11^(high))also have to endure the significant cost associated with SLC7A11-mediated metabolic reprogramming,leading to glucose-and glutamine-dependency in SLC7A11^(high) cancer cells,which presents potential metabolic vulnerabilities for therapeutic targeting in SLC7A11^(high) *** this review,we summarize diverse regulatory mechanisms of SLC7A11 in cancer,discuss ferroptosis-dependent and-independent functions of SLC7A11 in promoting tumor development,explore the mechanistic basis of SLC7A11-induced nutrient dependency in cancer cells,and conceptualize therapeutic strategies to target SLC7A11 in cancer *** review will provide the foundation for further understanding SLC7A11 in ferroptosis,nutrient dependency,and tumor biology and for developing novel effective cancer therapies.

关键词： SLC7A11 xCT cystine cysteine ferroptosis nutrient dependency cancer therapy

Effects of mixture ratio on anaerobic co-digestion with fruit and vegetable waste and food waste of China

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Journal of Environmental Sciences 2011年第8期23卷 1403-1408页

作者： Jia Lin Jiane Zuo Lili gan Peng Li Fenglin Liu Kaijun Wang Lei Chen Hainan gan State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC) School of EnvironmentTsinghua'University Beijing 100084 China. Joint R & D Ceter of Tsinghua Univesity (Department of Environmental Science and Engineering) andShandong Sifon Environmental Protection & Bio-Energy Co. Ltd. Beijing 100084 China

The biochemical methane potentials for typical fruit and vegetable waste （FVW） and food waste （FW） from a northern China city were investigated, which were 0.30, 0.56 m3 CH4/kgVS （volatile solids） with biodegradabilities of 59.3% and 83.6%, respectively. Individual anaerobic digestion testes of FVW and FW were conducted at the organic loading rate （OLR） of 3 kg VS/（m3-day） using a lab-scale continuous stirred-tank reactor at 35°C. FVW could be digested stably with the biogas production rate of 2.17 ma/（m3-day） and methane production yield of 0.42 m3 CH4/kg VS. However, anaerobic digestion process for FW was failed due to acids accumulation. The effects of FVW： FW ratio on co-digestion stability and performance were further investigated at the same OLR. At FVW and FW mixing ratios of 2：1 and 1：1, the performance and operation of the digester were maintained stable, with no accumulation of volatile fatty acids （VFA） and ammonia. Changing the feed to a higher FW content in a ratio of FVW to FW 1：2, resulted in an increase in VFAs concentration to 1100-1200 rag/L, and the methanogenesis was slightly inhibited. At the optimum mixture ratio 1：1 for co-digestion of FVW with FW, the methane production yield was 0.49 m3 CH4/kg VS, and the volatile solids and soluble chemical oxygen demand （sCOD） removal efficiencies were 74.9% and 96.1%, respectively.

关键词： anaerobic co-digestion biochemical methane potential continuous stirred-tank reactor (CSTR) fruit and vegetable waste food waste

A novel task-oriented framework for dual-arm robotic assembly task

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Frontiers of Mechanical Engineering 2021年第3期16卷 528-545页

作者： Zhengwei WANG Yahui gan Xianzhong DAI School of Automation Southeast UniversityNanjing 210096China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationNanjing 210096China

In industrial manufacturing,the deployment of dual-arm robots in assembly tasks has become a ***,making the dual-arm robots more intelligent in such applications is still an open,challenging *** paper proposes a novel framework that combines task-oriented motion planning with visual perception to facilitate robot deployment from perception to execution and finish assembly problems by using dual-arm *** this framework,visual perception is first employed to track the effects of the robot behaviors and observe states of the workpieces,where the performance of tasks can be abstracted as a high-level state for intelligent *** assembly task and manipulation sequences can be obtained by analyzing and reasoning the state transition trajectory of the environment as well as the ***,the corresponding assembly manipulation can be generated and parameterized according to the differences between adjacent states by combining with the prebuilt knowledge of the *** are set up with a dual-arm robotic system(ABB YuMi and an RGB-D camera)to validate the proposed *** results demonstrate the effectiveness of the proposed framework and the promising value of its practical application.

关键词： dual-arm assembly Al reasoning intelligent system task-oriented motion planning visual perception