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Transport of velocity alignment particles in random obstacles

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Chinese Physics B 2018年第8期27卷 164-169页

作者： wei-jing zhu Xiao-qun Huang Bao-quan Ail Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal University Basic Teaching Department Neusoft Institute Guangdong

We numerically investigate the trapping behaviors of aligning particles in two-dimensional （2D） random obstacles system. Under the circumstances of the effective diffusion rate and the average velocity tend to zero, particles are in trapped state. In this paper, we examine how the system parameters affect the trapping behaviors. At the large self-propelled speed, the ability of nematic particles escape from trapping state is enhancing rapidly, in the meanwhile the polar and free particles are still in trapped state. For the small rotation diffusion coefficient, the polar particles circle around （like vortices） the obstacles and here particles are in trapped state. Interestingly, only the partial nematic particles are trapped in the confined direction and additional particles remain flowing. In the free case, the disorder particle-particle collisions impede the motion in each other＇s directions, leading the free particles to be trapped. At the large rotation diffusion coefficient, the ordered motion of aligning particles disappear, particles fill the sample evenly and are self-trapped around obstacles. As the particles approach the trapping density due to the crowding effect the particles become so dense that they impede each other＇s motion. With the increasing number of obstacles, the trajectories of particles are blocked by obstacles, which obstruct the movement of particles. It is worth noting that when the number of the obstacles are large enough, once the particles are trapped, the system is permanently absorbed into a trapped state.

关键词： Brownian motion self-propelled particles stochastic processes

Endovascular treatment of acute proximal deep venous thrombosis secondary to iliac vein compression syndrome： a novel technique for thrombus removal

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Chinese Medical Journal 2013年第16期126卷 3184-3186页

作者： WANG Yi-ping ZHANG Xi-quan YU wei-na HAO Bin REN Ke-wei PAN jing-jing zhu Liang Department of Interventional Vascular the 148th Hospital of ChinesePeople's Liberation Army Zibo Shandong 255300 China

Iliac vein compression syndrome （IVCS）,also known as May-Thurner syndrome or Cockett syndrome,is caused by compression of the left common iliac vein between the right common iliac artery and the vertebrae.A recent imaging study have demonstrated that at least a 25%compression of the left iliac vein at the arterial crossover point may be present in 66% of the asymptomatic patient population.1 With the development of interventional technique,endovascular management as a less invasive means is becoming the first-line treatment,which can not only treat the thrombosis but also correct the venous anatomic abnormalities.2 In this study,we described a novel technique combining percutaneous aspiration thrombectomy （PAT） with Fogarty catheter thrombectomy （FCT） as the thrombus removal therapy without femoral venotomy in patients with acute deep vein thrombosis （DVT） due to IVCS and evaluated its technical feasibility and short-term outcomes.

关键词： iliac vein compression syndrome deep venous thrombosis percutaneous aspiration thrombectomy fogarty catheter thrombectomy

RAFT Miniemulsion Polymerization of MMA with Cumyl Dithiobenzoate as Chain Transfer Agent

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Chinese Chemical Letters 2006年第9期17卷 1247-1250页

作者： Tian Ying GUO Dong Lin TANG jing wei zhu Mou Dao SONG Bang Hua ZHANG Key Laboratory of Functional Polymer Materials Ministry of Education Institute of Polymer Chemistry Nankai University Tianjin 300071

Reversible addition-fragmentation transfer （RAPT） miniemulsion polymerizations for PMMA with cumyl dithiobenzoate （CDB） as a chain transfer agent （CTA） has been carried out. Higher temperature made the polymeriz... 详细信息

关键词： RAFT polymerization miniemulsion chain transfer agent cumyl dithiobenzoate.

Synergistic catalysis of the N-hydroxyphthalimide on flower-like bimetallic metal-organic frameworks for boosting oxidative desulfurization

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Petroleum Science 2024年第1期21卷 674-682页

作者： jing He Kun zhu wei Jiang Dong-Ao zhu Lin-Hua zhu Hai-Yan Huang Wen-Shuai zhu Hua-Ming Li Institute for Energy Research Jiangsu UniversityZhenjiang212013JiangsuChina College of Chemistry and Chemical Engineering Hainan Normal UniversityKey Laboratory of Water Pollution Treatment and Resource Reuse of Hainan ProvinceHaikou571158HainanChina

Synergic catalytic effect between active sites and supports greatly determines the catalytic activity for the aerobic oxidative desulfurization of fuel *** this work,Ni-doped Co-based bimetallic metal-organic framework(CoNi-MOF)is fabricated to disperse N-hydroxyphthalimide(NHPI),in which the whole catalyst provides plentiful synergic catalytic effect to improve the performance of oxidative desulfurization(ODS).As a bimetallic MOF,the second metal Ni doping results in the flower-like morphology and the modification of electronic properties,which ensure the exposure of NHPI and strengthen the synergistic effect of the overall *** with the monometallic Co-MOF and naked NHPI,the NHPI@CoNi-MOF triggers the efficient activation of molecular oxygen and improves the ODS performance without an *** sulfur removal of dibenzothiophene-based model oil reaches 96.4%over the NHPI@CoNi-MOF catalyst in 8 h of ***,the catalytic product of this aerobic ODS reaction is sulfone,which is adsorbed on the catalyst surface due to the difference in *** work provides new insight and strategy for the design of a strong synergic catalytic effect between NHPI and bimetallic supports toward high-activity aerobic ODS materials.

关键词： Metal-organic frameworks Doped Bimetallic N-hydroxyphthalimide Aerobic processes Oxidative desulfurization

Data-driven production optimization using particle swarm algorithm based on the ensemble-learning proxy model

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Petroleum Science 2023年第5期20卷 2951-2966页

作者： Shu-Yi Du Xiang-Guo Zhao Chi-Yu Xie jing-wei zhu Jiu-Long Wang Jiao-Sheng Yang Hong-Qing Song School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China National&Local Joint Engineering Lab for Big Data Analysis and Computer Technology Beijing100190China CNPC International Hong Kong Limited Abu DhabiUnited Arab Emirates Computer Network Information Center Chinese Academy of SciencesBeijing065007China China National Petroleum Corporation Langfang065007HebeiChina

Production optimization is of significance for carbonate reservoirs,directly affecting the sustainability and profitability of reservoir *** physics-based numerical simulations suffer from insufficient calculation accuracy and excessive time consumption when performing production *** establish an ensemble proxy-model-assisted optimization framework combining the Bayesian random forest(BRF)with the particle swarm optimization algorithm(PSO).The BRF method is implemented to construct a proxy model of the injectioneproduction system that can accurately predict the dynamic parameters of producers based on injection data and production *** the help of proxy model,PSO is applied to search the optimal injection pattern integrating Pareto front *** experimental testing,the proxy model not only boasts higher prediction accuracy compared to deep learning,but it also requires 8 times less time for *** addition,the injection mode adjusted by the PSO algorithm can effectively reduce the gaseoil ratio and increase the oil production by more than 10% for carbonate *** proposed proxy-model-assisted optimization protocol brings new perspectives on the multi-objective optimization problems in the petroleum industry,which can provide more options for the project decision-makers to balance the oil production and the gaseoil ratio considering physical and operational constraints.

关键词： Production optimization Random forest The Bayesian algorithm Ensemble learning Particle swarm optimization

Ratchet transport of overdamped particles in superimposed driven lattices

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Chinese Physics B 2019年第4期28卷 108-112页

作者： Shu-Na Huang wei-jing zhu Xiao-Qun Huang Bao-Quan Ai Feng-Guo Li Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal University

Ratchet transport of overdamped particles is investigated in superimposed driven lattices using Langevin dynamics simulations. It is found that noise can strongly affect the transport of the particles. When lattices driving dominates the transport, the noise acts as a disturbance of the directed transport and slows down the average velocity of the *** the driving phase has less impact on particle transport, Gaussian white noise can play a positive role. By simply modulating these two parameters, we can control efficiency and the direction of the directed currents.

关键词： Gaussian white noise superimposed driven lattices rectification

A function-based behavioral modeling method for air combat simulation

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Journal of Systems Engineering and Electronics 2024年第4期35卷 945-954页

作者： WANG Tao zhu Zhi ZHOU Xin jing Tian CHEN wei College of Systems Engineering National University of Defense TechnologyChangsha 410073China Institute of Communication and Navigation Air Force Research AcademyBeijing 100085China

Today’s air combat has reached a high level of uncertainty where continuous or discrete variables with crisp values cannot be properly represented using fuzzy sets. With a set of membership functions, fuzzy logic is well-suited to tackle such complex states and actions. However, it is not necessary to fuzzify the variables that have definite discrete ***, the aim of this study is to improve the level of model abstraction by proposing multiple levels of cascaded hierarchical structures from the perspective of function, namely, the functional decision tree. This method is developed to represent behavioral modeling of air combat systems, and its metamodel,execution mechanism, and code generation can provide a sound basis for function-based behavioral modeling. As a proof of concept, an air combat simulation is developed to validate this method and the results show that the fighter Alpha built using the proposed framework provides better performance than that using default scripts.

关键词： air combat behavioral modeling intelligent agent

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： TIAN jing ZHANG wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

High-pressure minerals and new lunar mineral changesite-(Y) in Chang’e-5 regolith

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Matter and Radiation at Extremes 2024年第2期9卷 90-97页

作者： jing Yang wei Du Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences(CAS)Guiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide opportunities to address some key scientific questions related to theMoon, including the discovery of high-pressure silica polymorphs (seifertite and stishovite) and a new lunar mineral, changesite-(Y). Seifertitewas found to be coexist with stishovite in a silica fragment from CE-5 lunar regolith. This is the first confirmed seifertite in returned lunarsamples. Seifertite has two space group symmetries (Pnc2 and Pbcn) and formed from an α-cristobalite-like phase during “cold” compressionduring a shock event. The aftershock heating process changes some seifertite to stishovite. Thus, this silica fragment records different stagesof an impact process, and the peak shock pressure is estimated to be ∼11 to 40 GPa, which is much lower than the pressure condition forcoexistence of seifertite and stishovite on the phase diagram. Changesite-(Y), with ideal formula (Ca_(8)Y)◻Fe^(2+)(PO_(4))_(7) (where ◻ denotes avacancy) is the first new lunar mineral to be discovered in CE-5 regolith samples. This newly identified phosphate mineral is in the form ofcolumnar crystals and was found in CE-5 basalt fragments. It contains high concentrations of Y and rare earth elements (REE), reaching upto ∼14 wt. % (Y,REE)2O3. The occurrence of changesite-(Y) marks the late-stage fractional crystallization processes of CE-5 basalts combinedwith silicate liquid immiscibility. These new findings demonstrate the significance of studies on high-pressure minerals in lunar materials andthe special nature of lunar magmatic evolution.

关键词： evolution minerals basalt