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Pyramid scheme model for consumption rebate frauds

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Chinese Physics B 2019年第7期28卷 549-556页

作者： yong Shi Bo Li Wen long School of Economics and Management University of Chinese Academy of Sciences Beijing 100190 China Research Center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing 100190 China Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of Sciences Beijing 100190 China

There are various types of pyramid schemes that have inflicted or are inflicting losses on many people in the *** propose a pyramid scheme model which has the principal characters of many pyramid schemes that have appeared in recent years: promising high returns, rewarding the participants for recruiting the next generation of participants, and the organizer takes all of the money away when they find that the money from the new participants is not enough to pay the previous participants interest and *** assume that the pyramid scheme is carried out in the tree network, Erd?s–Réney(ER) random network, Strogatz–Watts(SW) small-world network, or Barabasi–Albert(BA) scale-free *** then give the analytical results of the generations that the pyramid scheme can last in these *** also use our model to analyze a pyramid scheme in the real world and we find that the connections between participants in the pyramid scheme may constitute a SW small-world network.

关键词： pyramid scheme complex networks small-world networks

Experimental study and characteristic finite element simulation of solute transport in a cross-fracture

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Geoscience Frontiers 2016年第6期7卷 963-967页

作者： long-fei Chen yong Huang Civil Engineering department of Chongqing Three Gorges College Wanzhou 404000China School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China

A new method, the characteristic finite element method （CFEM）, was developed to simulate solute transport in a cross-fracture. The solution of this mathematical model for solute transport considered that the contribution of convection and dispersion terms was deduced using the single-step, trace-back method and routine finite element method （FEM）. Also, experimental models were designed to verify the reliability and validity of the CFEM. Results showed that experimental data from a single fracture model agreed with numerical simulations obtained from the use of the CFEM. However, routine FEM caused numerical oscillation and dispersion during the calculation of solute concentration. Furthermore, in this cross-fracture model, CFEM simulation results predicted that the arrival time of concentration peak values decreased with increasing flux. Also, the second concentration peak value was obvious with the decrease of flux, which may have resulted from the convergence of solute concentrations from main, and branch, fractures.

关键词： Solute transport Cross-fracture CFEM Dispersion

Glutamatergic CYLD deletion leads to aberrant excitatory activity in the basolateral amygdala:association with enhanced cued fear expression

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Neural Regeneration Research 2025年第11期20卷 3259-3272页

作者： Huidong Li Faqin Li Zhaoyi Chen Erwen Wu Xiaoxi Dai Danni Li Haojie An Shiyi Zeng Chunyan Wang Li Yang Cheng long School of Life Sciences South China Normal UniversityGuangzhouGuangdong ProvinceChina School of Life Sciences Guangzhou UniversityGuangzhouGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Major Obstetric Diseases The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina South China Normal University-Panyu Central Hospital Joint Laboratory of Translational Medical Research Panyu Central HospitalGuangzhouGuangdong ProvinceChina

Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear ***(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B *** is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly *** studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like ***,the precise role of CYLD in glutamatergic neurons is largely ***,we first proposed involvement of CYLD in cued fear *** next constructed transgenic model mice with specific deletion of Cyld from glutamatergic *** results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male ***,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male ***,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial *** may contribute,at least in part,to cued fear expression.

关键词： basolateral amygdala cued fear expression cylindromatosis deubiquitinase glutamate receptor 1 glutamatergic neuron microglial activation N-methyl-D-aspartate receptor 1 neuronal activation synaptic transmission

Effect of source size and emission time on the p–p momentum correlation function in the two-proton emission process

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Nuclear Science and Techniques 2020年第5期31卷 64-69页

作者： long Zhou de-Qing Fang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China

The effect of source size and emission time on the proton-proton(p-p)momentum correlation function(Cpp(q))has been studied *** a spherical Gaussian source with space and time profile according to the function S(r,t)~exp(-r2/2 r02-t/τ)in the correlation function calculation code(CRAB),the results indicate that one Cpp(q)distribution corresponds to a unique combination of source size r0 and emission timeτ.Considering the possible nuclear deformation from a spherical nucleus,an ellipsoidal Gaussian source characterized by the deformation parameter∈=ΔR/R has been *** is almost no difference of Cpp(q)between the results of spherically and ellipsoidally shaped sources with small *** results indicate that a unique source size r0 and emission time could be extracted from the p-p momentum correlation function,which is especially important for identifying the mechanism of twoproton emission from proton-rich ***,considering the possible existence of cluster structures within a nucleus,the double Gaussian source is *** results show that the p-p momentum correlation function for a source with or without cluster structures has large systematical differences with the variance of r0 andτ.This may provide a possible method for experimentally observing the cluster structures in proton-rich nuclei.

关键词： Two-proton emission p–p momentum correlation function Source size Emission time

Theoretical investigations of transport properties of organic solvents in cation-functionalized graphene oxide membranes： Implications for drug delivery

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Nano Research 2018年第1期11卷 254-263页

作者： Kai Song yong long Xun Wang Gang Zhou State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Key Lab of Organic Optoelectronics and Molecular Engineering Department of Chemistry Tsinghua University Beijing 100084 China

We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide （M-GO） membranes to organic solvents. The results show that the selectivity is associated mainly with the transport properties of solvents in the membranes, which depends on two regions of the flow path： the sp3 C-O matrix of the GO sheets and the cation at the center of the hexagon rather than the sp~ region. According to the delocalization of ~ states in sp2 regions, we propose a design guide for high-quality M-GO membranes. The solvent-cation interaction essentially causes directional transport of molecules in the M-GO membranes under the transmembrane pressure, indicating a site-to-site mech- anism. The solvent-sp3 C-O matrix interaction may inhibit molecular transport between two fixed cations by consuming energy. The competition between energy consumption by the solvent-cation interaction and energy expenditure by the solvent-sp3 C-O matrix interaction leads to various transport properties of solvents and thus allows for the selective permeability of the M-GO membranes. Findings from the study are helpful for the future design of multifunctional M-GO macro-membranes as cost-effective solution nanofilters in chemical, biological, and medical applications

关键词： alkali and alkaline earthcation-decorated grapheneoxide (M-GO) membrane organic solvent permeability transport density functional theory

Controller area network node reliability assessment based on observable node information

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 615-626页

作者： Lei-ming ZHANG long-hao TANG yong LEI State Key Laboratory of Fluid Power Transmission and Mechatronics Zhejiang UniversityHangzhou 310027China

Controller area network(CAN) based fieldbus technologies have been widely used in networked manufacturing systems. As the information channel of the system, the reliability of the network is crucial to the system throughput, product quality, and work crew safety. However, due to the inaccessibility of the nodes' internal states, direct assessment of the reliability of CAN nodes using the nodes' internal error counters is infeasible. In this paper, a novel CAN node reliability assessment method, which uses node's time to bus-off as the reliability measure, is proposed. The method estimates the transmit error counter(TEC) of any node in the network based on the network error log and the information provided by the observable nodes whose error counters are ***, a node TEC estimation model is established based on segmented Markov chains. It considers the sparseness of the distribution of the CAN network errors. Second, by learning the differences between the model estimates and the actual values from the observable node, a Bayesian network is developed for the estimation updating mechanism of the observable nodes. Then, this estimation updating mechanism is transferred to general CAN nodes with no TEC value accessibility to update the TEC estimation. Finally, a node reliability assessment method is developed to predict the time to reach bus-off state of the nodes. Case studies are carried out to demonstrate the effectiveness of the proposed methodology. Experimental results show that the estimates using the proposed model agree well with actual observations.

关键词： Controller area network(CAN) Transmit error counter(TEC) TEC value estimation Bayesian network Bus-off hitting time

Learning real-time search on c-space GVDs

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Frontiers of Computer Science 2017年第6期11卷 1036-1049页

作者： Quanjun YIN long QIN yong PENG Wei DUAN College of Information System and Management National University of Defense Technology Changsha 410073 China

In the context of robotics, configuration space （c- space） is widely used for non-circular robots to engage tasks such as path planning, collision check, and motion planning. In many real-time applications, it is important for a robot to give a quick response to the user＇s command. Therefore, a constant bound on planning time per action is severely im- posed. However, existing search algorithms used in c-space gain first move lags which vary with the size of the under- lying problem. Furthermore, applying real-time search algo- rithms on c-space maps often causes the robots being trapped within local minima. In order to solve the above mentioned problems, we extend the learning real-time search （LRTS） algorithm to search on a set of c-space generalized Voronoi diagrams （c-space GVDs）, helping the robots to incremen- tally plan a path, to efficiently avoid local minima, and to ex- ecute fast movement. In our work, an incremental algorithm is firstly proposed to build and represent the c-space maps in Boolean vectors. Then, the method of detecting grid-based GVDs from the c-space maps is further discussed. Based on the c-space GVDs, details of the LRTS and its implemen- tation considerations are studied. The resulting experiments and analysis show that, using LRTS to search on the c-space GVDs can 1） gain smaller and constant first move lags which is independent of the problem size; 2） gain maximal clear- ance from obstacles so that collision checks are much re- duced; 3） avoid local minima and thus prevent the robot from visually unrealistic scratching.

关键词： generalized Voronoi diagrams real-time search,robotics configuration space incremental algorithms

A reconstructed edge-based smoothed DSG element based on global coordinates for analysis of Reissner–Mindlin plates

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Acta Mechanica Sinica 2017年第1期33卷 83-105页

作者： Gang Yang de’an Hu Shuyao long State Key Laboratory of Advanced design and Manufacturing for Vehicle Body College of Mechanical and Vehicle Engineering Hunan University Changsha 410082China

A reconstructed edge-based smoothed triangular element, which is incorporated with the discrete shear gap (DSG) method, is formulated based on the global coordinate for analysis of Reissner-Mindlin plates. A symbolic integration combined with the smoothing technique is implemented to calculate the smoothed finite element matrices, which is integrated along the boundaries of each smoothing cell. Numerical results show that the proposed element is free from shear locking, and its results are in good agreement with the exact solutions, even for very thin plates with extremely distorted elements. The proposed element gives more accurate results than the original DSG element without smoothing, and it can be taken as an alternative element for analysis of Reissner-Mindlin plates. The prominent feature of the present element is that the integration scheme is unified in the smoothed form for all of the finite element matrices.

关键词： Reissner-Mindlin plate DSG method Symbolic integration Smoothing technique Global coordinate Distorted element

Effects of Mg/PTFE pyrotechnic compositions on reignition characteristics of base bleed propellants and heating mechanism

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defence Technology（防务技术） 2022年第1期18卷 94-108页

作者： Xiao-chun Xue long-ze Ma yong-gang Yu Schooi of Enerey and Power Engineering Nanjing Universiry of Science and Techmology Narine lianesu 210094 China BYD Compary Liruied ShenzheL Guanedong 518118 Chna

The effects of magnesium/polytetrafluoroethylene(Mg/PTFE)pyrotechnic compositions on the coupled flow field and reignition mechanism are important aspects governing the perfommance and range of base bleed projectiles(BBPs).Owing to a decrease in pressure and temperature when the BBP leaves the muzzle,rapid depressurization occurs,which extinguishes the base bleed *** Mg/PTFE py-rotechnic composition pressed in the igniter of the base bleed unit(BBU)provides additional energy to the BBU via a chemical ***,the extinguished base bleed propellant is reignited under the effect of high-temperature combustion gas jets from the *** this study,a numerical analysis is conducted to evaluate the effects of PTFE and Mg granularity as well as Mg/PTFE pyrotechnic *** to the rapid depressurization,the temperature and pressure was found to decrease fordifferent Mg/PIFE pyrotechnic ***,the depressurization time increased as the PTFE granularity increased,the Mg granularity decreased,and the Mg content *** the pressure in the combustion chamber of the BBU decreased to the atmospheric pressure,the combustion gas jets from the igniter expand upstream(rather than downstream).However,these combustion gas jets exhibit different axial and radial expansion characteristics depending on the pyrotechnic compositions used,The results show that the reignition delay time,ta,of the base bleed propellant was 377.608,94.27,387.243,523.966,and 221.094 ms for cases A-E,***,it was concluded that the Mg/PTFE pyrotechnic composition of case B was the most beneficial for the reignition of the base bleed propellant,with the earliest addition of energy and mass to the BBP.

关键词： Thermal effect High-temperature combustion gas Mg/PTFE pyrotechnic Compositions Reignition