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Probabilistic model of disc-cutter wear in TBM construction:A case study of Chaoer to Xiliao water conveyance tunnel in China

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Science China(Technological Sciences) 2023年第12期66卷 3534-3548页

作者： YANG WenKun CHEN ZuYu WU GenSheng xing hai School of Civil Engineering Institute of Future Underground SpaceSoutheast UniversityNanjing 211189China Department of Geotechnical Engineering China Institute of Water Resources and Hydropower ResearchBeijing 100038China Sinohydro Bureau 6 Co. Ltd.Shenyang 110179China

Disc-cutters play a crucial role in the penetration process during construction using a tunnel boring machine(TBM).Their wear status has a significant impact on working efficiency and costs that accounts for a large part of the *** the wear pattern and characteristics of disc-cutters could provide a valuable guide for field maintenance and cutter replacement *** also provides insight into the wear mechanism of cutters at different positions for optimizing the disc-cutter arrangement *** this study,the cutter wears data of 34 disc-cutters over 643 days in the Chaoer River to Xiliao River water diversion tunnel was *** dataset contains 21862 manual readings measured from 1079 disc-cutters replaced in this *** raw data from the hard copy version was transformed into a digital twin database by eliminating abnormal data,filling in empty values,and performing linear *** has been found that the cutters can pass statistical testing for an exponential probability distribution function with respect to the wear rate(w).The regression ratios of R2are essentially greater than *** findings would help estimate the future service life of a currently working cutter,which means significant savings for the costly *** application of exponential distribution has the advantage of only one shape parameter,λ,whose reciprocal represents both the statistical mean and standard deviation of the wear *** is simple and practically amenable.A preliminary study was carried out to simulate the wear process between two neighboring cutters for drafting a replacement plan for disc-cutters by the Monte Carlo *** prediction results agreed reasonably well with the measured information.

关键词： tunnel boring machine disc-cutter wear wear rate probability model

On Corepresentations of Multiplier Hopf Algebras

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Acta Mathematica Sinica,English Series 2010年第6期26卷 1087-1114页

作者： Shuan-hong WANG hai-xing ZHU Department of Mathematics Southeast University Nanjing 210096 P. R. China

We present a general construction producing a unitary corepresentation of a multiplier Hopf algebra in itself and study RR-corepresentations of twisted tensor coproduct multiplier Hopf algebra. Then we investigate some properties of functors, integrals and morphisms related to the categories of the crossed modules and covariant modules over multiplier Hopf algebras. By doing so, we can apply our theory to the case of group-cograded multiplier Hopf algebras, in particular, the case of Hopf group-coalgebras.

关键词： (group-cograded) multiplier Hopf algebra copresentation crossed module covariant module Hopf group-coalgebra twisted tensor coproduct

Transport Properties of Lithium Plasma

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Chinese Physics Letters 2012年第2期29卷 138-140页

作者： CHEN Shi-Qiang WANG hai-xing School of Astronautics Beijing University of Aeronautics and AstronauticsBeijing 100191

Transport properties of lithium plasmas in local thermodynamic equilibrium at pressures from 0.0001 atm to 1 atm,and temperatures from 1000K to 40000K are *** calculations of transport coefficients are carried out using the Chapman-Enskog *** evolutions of transport coefficients with temperature and pressure are reported and *** of these values in the low temperature region with previously reported data show reasonable agreement.

关键词： method Lithium lithium

On the Seidel Integral Complete Multipartite Graphs

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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 705-710页

作者： Sheng-mei LV Liang WEI hai-xing ZHAO Department of Mathematics Qinghai Nationality University Department of Mathematics Qinghai Normal University

For a simple undirected graph G, denote by λ（G） the （0, 1）-adjacency matrix of G. Let the matrix S（G） = J-I-2A（G） be its Seidel matrix, and let SG（A） = det（AI-S（G）） be its Seidel characteristic polynomial, where I is an identity matrix and J is a square matrix all of whose entries are equal to 1. If all eigenvalues of SG（λ） are integral, then the graph G is called S-integral, In this paper, our main goal is to investigate the eigenvalues of SG（A） for the complete multipartite graphs G = Kn1,n2,...,n,. A necessary and sufficient condition for the complete tripartite graphs Km,n,t and the complete multipartite graphs Km,.... m,n,...,n to be S-integral is given, respectively.

关键词： S-polynomial S-integral complete multipartite graphs

Improving the design of reinforcing frames by simulating the arch and peltate venation structures

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Journal of Beijing Institute of Technology 2014年第1期23卷 29-36页

作者： xing Deng-hai CHEN Wu-yi School of Mechanical Engineering and Automation Beihang University Beijing 100191 China Fly Control Department Flight Automatic Control Research Institute Xi'an 710055 China

Based on the analyses on arch and peltate venation structures, the design of reinforcing frames was improved. First, distribution rules of the arch structure were summarized. According to the load condition and the structure of the frame, a mechanical model of arch structure was devel- oped, and two solutions for the model were analyzed and compared with each other. Through the a- nalysis, application rules of arch structure for improving the design were obtained. Then, distribu- tion rules of peltate venation structure were summarized. By using the same method, application rules of peltate venation structure for improving the design were also obtained. Finally, mechanical problem of the frame was described, and rib arrangement of the frame was redesigned. A parameter optimization for the widths of ribs in bionic arrangement was also carried out to accomplish the im- proving design. Comparison between bionic and conventional reinforcing frames shows that the weight is reduced by as much as 15.3%.

关键词： improving design lightweight reinforcing frame arch structure peltate venation bionic design

Modified Cascade Synchronization Scheme for Discrete-Time Hyperchaotic Systems

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Communications in Theoretical Physics 2008年第10期50卷 919-924页

作者： ZHU hai-xing LI Yong-Zhi AN Hong-Li Department of Mathematics Southeast University Nanjing 210096 China Department of Computer Science and Engineering Nanjing Forestry University Nanjing 210037 China Nonlinear Science Center and Department of Mathematics Ningbo University Ningbo 315211 China

In this paper, the modified cascade synchronization scheme is proposed to investigate the synchronization in discrete-time hyperchaotic systems. By choosing a general kind of proportional scaling error functions and based on rigorous control theory, we take the discrete-time hyperchaotic system due to Wang and 3D generalized Henon map as two examples to achieve the modified cascade synchronization, respectively. Numerical simulations are used to verify the effectiveness of the proposed technique.

关键词： chaos synchronization discrete-time hyperchaotic systems modified cascade synchronization

Binding property of Al/Mg/Al thin plates fabricated by one-pass hot rolling with different reduction ratios,temperatures and annealing treatments

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Rare Metals 2018年第2期37卷 136-142页

作者： Ai-Li Wei xing-hai Liu Li Dong Wei Liang School of Materials Science and Engineering Taiyuan University of Technology

In this study, Al-Mg-Al trilaminated thin plates were fabricated by one-pass hot rolling to improve the processing capacity and bonding strength of magne- sium alloy plates. The effects of processing parameters were investigated. The results show that the optimal bonding strength is up to 20 MPa with a reduction ratio of 40 % and rolling temperature of 400 ℃, superior than that in other one-pass rolling studies with regard to thin lami- nated plates. In addition, a favorable property is achieved with the annealing temperature of 250-300 ℃ or annealing time of 1.5 h. When the annealing temperature exceeds 300 ℃ or annealing time exceeds 1.5 h, respectively, the bonding strength of Al/Mg/Al plate decreases. The scan- ning electron microscopy （SEM） and energy-dispersive spectroscopy （EDS） analyses suggest that the appearance of thin diffusion layers between Al and Mg interfaces is helpful to improve the bonding strength, while the presence of thick diffusion layer would reduce the bonding strength greatly.

关键词： Al-Mg-Al thin plates One-pass rolling Bonding strength Mesophase Microstructure

Mechanisms for non-ideal flow in low-power arc-heated supersonic nozzles

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Acta Mechanica Sinica 2015年第4期31卷 500-511页

作者： Cheng-Kang Wu Wen-Xia Pan Xian Meng hai-xing Wang State Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences School of Astronautics Beijing University of Aeronautics and Astronautics

The flow in a low-powered arc gas heater com- bined with a supersonic nozzle of throat diameter less than 1 mm is quite complicated and difficult to describe in quan- titative detail. Experiments on arc-heated supersonic jet thrusters of monatomic gases argon and helium have been carried out and their performance measured. The flow charac- teristics are analyzed with the help of numerical simulation. Results show that the viscous effect is the most important factor causing the large difference between ideal and real performance. A large outer section of the exit flow is slow- moving. This is especially pronounced in helium, where 70 % of the exit area of the nozzle might be in subsonic flow. Fric- tion forces can be much larger than the net thrust, reaching several times higher in helium, resulting in very low efficien- cies. Other factors causing the differences between ideal and real flow include： complex flow in the throat region, electric arc extending to the nozzle expansion section, heat transfer to the inlet gas and from the hot plasma, and environmen- tal pressure in the vacuum chamber. It is recognized that the ordinary concepts of supersonic nozzle flow must be greatly modified when dealing with such complicated situations. The general concepts presented in this paper could be helpful in guiding the design and operation of this equipment.

关键词： Arc-heated supersonic jet Low-power Real flow Viscosity effect Low Reynolds number

Mechanisms underlying aspirin-mediated growth inhibition and apoptosis induction of cyclooxygenase-2 negative colon cancer cell line SW480

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World Journal of Gastroenterology 2008年第26期14卷 4227-4233页

作者： Ming-Yu Lai Jie-An Huang Zhi-hai Liang hai-xing Jiang Guo-Du Tang Department of Gastroenterology First Affiliated Hospital Guangxi Medical University Nanning 530021Guangxi Zhuang Autonomous Region China

AIM： To investigate the effects of aspirin （acetylsalicylic acid） on proliferation and apoptosis of colorectal cancer cell line SW480 and its mechanism. METHODS： Cyclooxygenase （COX）-2 negative colorectal cancer cell line SW480 was treated with aspirin at concentrations of 2.5 mmol/L, 5.0 mmol/L, 10.0 mmol/L for different periods in v/tro. Anti-proliferation effect of aspirin on SW480 was detected by 3-（4,5-dimeth- ylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay. Cell cycle and apoptosis were observed by flow cytometry （FCM）. Transmission electron microscope （TEM） was used for morphological study. Apoptosis-associated genes were detected by immunohistochemical staining and Western blotting. RESULTS： Aspirin inhibited SW480 proliferation and induced apoptosis in a dose- and time-dependent manner. Treatment with different concentrations of aspirin significantly increased the proportions of cells at the G0/G1 phase and decreased the proportions of cells at the S- and G2/M phases in a concentration-dependent manner. Aspirin not only induced apoptosis but also caused cell necrosis at a high concentration as well. After treatment with aspirin, SW480 cells displayed typically morphological features of apoptosis and necrosis under TEM, and increased the Bcl-2 expression in cells, but the expression of Bax was down regulated. CONCLUSION： Aspirin inhibits proliferation and induces apoptosis of SW480 cells. Its anti-tumor mechanism may arrest cell cycle and shift Bax/Bcl-2 balance in cells.

关键词： Aspirin Colorectal cancer Proliferation Apoptosis