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Modeling and multiobjective optimization of traction performance for autonomous wheeled mobile robot in rough terrain

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第1期14卷 11-29页

作者： Ozoemena Anthony ANI he xu Yi-ping SheN Shao-gang LIU Kai xuE College of Mechanical and Electrical Engineering Harbin Engineering University

Application of terrain-vehicle mechanics for determination and prediction of mobility performance of autonomous wheeled mobile robot （AWMR） in rough terrain is a new research area currently receiving much attention for both terrestrial and planetary missions due to its significant role in design, evaluation, optimization, and motion control of AWMRs. In this paper, decoupled closed form terramechanics considering important wheel-terrain parameters is applied to model and predict traction. Numerical analysis of traction performance in terms of drawbar pull, tractive efficiency, and driving torque is carried out for wheels of different radii, widths, and lug heights, under different wheel slips. Effects of normal forces on wheels are analyzed. Results presented in figures are discussed and used to draw some conclusions. Furthermore, a multiobjective optimization （MOO） method for achieving optimal mobility is presented. The MOO problem is formulated based on five independent variables in- eluding wheel radius r, width b, lug height h, wheel slip s, and wheel rotation angle 0 with three objectives to maximize drawbar pull and tractive efficiency while minimizing the dynamic traction ratio. Genetic algorithm in MATLAB is used to obtain opti- mized wheel design and traction control parameters such as drawbar pull, tractive efficiency, and dynamic traction ratio required for good mobility performance. Comparison of MOO results with experimental results shows a good agreement. A method to apply the MOO results for online traction and mobility prediction and control is discussed.

关键词： Autonomous wheeled mobile robot (AWMR) Terramechanics Traction Motion control Multiobjectiveoptimization (MOO) Genetic algorithm (GA)

Synthesis of New Thiazine and Thiosemicarbazone Derivatives from D-Xylose

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Chinese Chemical Letters 2006年第12期17卷 1563-1565页

作者： Xiao Ming JI he ping SUN Hai Wei xu Hong Min LIU New Drug Research ＆ Development Center Zhenzhou University Zhengzhou 450052

1,2-O-Isopropylidene-5-O-p-toluenesulfonyl-α-D-erythro-pentofuranos-3-ulose 1 was treated with thiourea and aminothiourea to give a D-ribose derivative 2 bearing a 2-amino 1,3-thiazine ring and a thiosemicarbazone derivative 5, respectively. 2 was acylated with Ac20 and propandioic acid to afford two acylation derivatives 3 and 4, respectively. Reduction of 5 with NaBH4 in methanol produced a hydrothiosemicarbazone derivative 6. The absolute configuration of 2 was confirmed by X-ray crystallographic analysis. The structures of all products were elucidated by IR, NMR and HRMS spectra.

关键词： Thiourea aminothiourea thiazine D-xylose synthesis.

A new maximum-likelihood phase estimation method for X-ray pulsar signals

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第6期15卷 458-469页

作者： Hua ZHANG Lu-ping xu Yang-he SheN Rong JIAO Jing-rong SUN School of Aerospace Science and Technology Xidian University

X-ray pulsar navigation(XPNAV) is an attractive method for autonomous navigation of deep space in the future. Currently, techniques for estimating the phase of X-ray pulsar radiation involve the maximization of the general non-convex object functions based on the average profile from the epoch folding method. This results in the suppression of useful information and highly complex computation. In this paper, a new maximum likelihood(ML) phase estimation method that directly utilizes the measured time of arrivals(TOAs) is presented. The X-ray pulsar radiation will be treated as a cyclo-stationary process and the TOAs of the photons in a period will be redefined as a new process, whose probability distribution function is the normalized standard profile of the pulsar. We demonstrate that the new process is equivalent to the generally used Poisson model. Then, the phase estimation problem is recast as a cyclic shift parameter estimation under the ML estimation, and we also put forward a parallel ML estimation method to improve the ML solution. Numerical simulation results show that the estimator described here presents a higher precision and reduces the computational complexity compared with currently used estimators.

关键词： X-ray pulsar Poisson model Phase estimation Maximum likelihood

hexyl substitution of pentathienoacene toward a significant improvement in charge transport

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Chinese Chemical Letters 2019年第4期30卷 903-905页

作者： ping he Hantang Zhang Chunhui xu Yonggang Zhen Huanli Dong Wenping Hu Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province China West Normal University Beijing National Laboratory for Molecular Science Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences College of Chemistry and Material Science Shandong Agriculture University Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of Chemistry School of Science Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)

A novel semiconductor, dihexyl-substituted pentathienoacene(C6-PTA) is designed and synthesized in five steps with the total yield up to 25.2%. The introduction of hexyl chains endow the thin film semiconductor with about threefold increase in carrier mobility and one to three orders of magnitude improvement in current on/off ratio. Furthermore, single crystal FETs based on C6-PTA exhibited mobility up to 0.64 cm^2 V^(-1) s^(-1), which is over 50 times higher than the thin film counterpart. The results indicate clearly that C6-PTA is a promising organic semiconductor with high stability.

关键词： Organic field-effect transistors Organic semiconductors Thienoacene Charge transport Stability

Application of dynamic vibration absorber for vertical vibration control of corrugated rolling mill

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Journal of Iron and Steel Research International 2023年第4期30卷 736-748页

作者： Dong-ping he Hui-dong xu Ming Wang Tao Wang Chao-ran Ren Zhi-hua Wang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment Ministry of EducationTaiyuan 030024ShanxiChina

A variable mass tuned particle absorber is designed for the nonlinear vertical vibration control of the corrugated rolling mill in the composite plate rolling *** the nonlinear damping and nonlinear stiffness between the corrugated interface,a three-degree-of-freedom nonlinear vertical vibration mathematical model of corrugated rolling mill based on dynamic vibration absorber control is *** multi-scale method is used to solve the amplitude–frequency characteristic curve equation of the installed dynamic vibration absorber(DVA)*** effects of stiffness coefficient and damping coefficient on the amplitude–frequency characteristic curve are *** expressions of the dynamic developed factor of the corrugated roll are derived,and the influence laws of mass ratio,frequency ratio and damping ratio on the dynamic amplification factor are *** optimal parameters of the DVA are obtained by adaptive genetic *** control effect of the DVA on the nonlinear vertical vibration is studied by numerical *** feasibility of the designed dynamic absorber is verified through *** results show that the designed dynamic absorber can effectively suppress the vertical vibration of the corrugated roller.

关键词： Corrugated rolling mill Nonlinear vertical vibration Adaptive genetic algorithm Multiscale method Dynamic vibration absorber

The inducible secreting TLR5 agonist,CBLB502,enhances the anti-tumor activity of CAR133-NK92 cells in colorectal cancer

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Cancer Biology & Medicine 2023年第9期20卷 662-681页

作者： Xiaohui Wang Wei Qiu Haoyu Liu Min he Wei he Zhan Li Zhiqiang Wu Xiang xu ping Chen College of Biotechnology Southwest UniversityChongqing 400715China Department of Stem Cell&Regenerative Medicine State Key Laboratory of TraumaBurn and Combined InjuryDaping HospitalArmy Medical UniversityChongqing 400042China Department of Dermatology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325035China Department of Biotherapeutics The First Medical CenterChinese PLA General HospitalBeijing 100038China

Objective:CAR-T/NK cells have had limited success in the treatment of solid tumors,such as colorectal cancer(CRC),in part because of the heterogeneous nature of tumor-associated antigens that lead to antigen-negative relapse after the initial *** barrier might be overcome by enhancing the recruitment and durability of endogenous immune ***:Immunohistochemistry and flow cytometry were used to assess the expression of CD133 antigen in tissue microarrays and cell lines,*** vector transduction was used to generate CBLB502-secreting CAR133-NK92 cells(CAR133-i502-NK92).The tumor killing capacity of CAR133-NK92 cells in vitro and in vivo were quantified via LDH release,the RTCA assay,and the degranulation test,as well as measuring tumor bioluminescence signal intensity in mice ***:We engineered CAR133-i502-NK92 cells and demonstrated that those cells displayed enhanced proliferation(9.0×10^(4)cells vs.7.0×10^(4)cells)and specific anti-tumor activities in vitro and in a xenogeneic mouse model,and were ***,CBLB502 secreted by CAR133-i502-NK92 cells effectively activated endogenous immune ***,in hCD133+/hCD133−mixed cancer xenograft models,CAR133-i502-NK92 cells suppressed cancer growth better than the counterparts(n=5,P=0.0297).Greater T-cell infiltration was associated with greater anti-tumor potency(Phe treatment of antigenically-diverse solid tumors.

关键词： TLR5 agonist CBLB502 CAR133 endogenous immune response colorectal cancer

Properties and structure of a new non-reactive mold flux for high-Al steel

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Journal of Iron and Steel Research International 2022年第1期29卷 61-70页

作者： Yang Chen Sheng-ping he Zhi-rong Li xu-bin Zhang Qiang-qiang Wang Qian Wang College of Materials Science and Engineering Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and Advanced MaterialsChongqing UniversityChongqing 400044China

During the conventional continuous casting process of high-aluminum steels(w([Al])>0.5 wt.%),some components of slag,such as SiO_(2),B_(2)O_(3),and TiO_(2),could be reduced by aluminum in molten ***,the CaO-BaO-Al_(2)O_(3)-CaF2-Li2O non-reactive mold fluxes were designed using the simplex grid method and molecular dynamics to mitigate the slag-metal interface reaction and stabilize the performance of mold *** results show that the components of nonreactive quinary system are 20-40 wt.% CaO,14-34 wt.% BaO,14-34 wt.% Al_(2)O_(3),4-12 wt.% F,and 4-8 wt.% Li_(2)*** dynamics simulation results show that[AlO_(4)]-tetrahedron acts as network formers and melt network structure is mainly chain and lamellar in the low-viscosity *** cross sections of w(F)=8 wt.%,w(Li_(2)O)=8 wt.%and w(F)=12 wt.%,w(Li2O)=8 wt.% are important reference sections for the design of mold flux,with the compositions of 22-40 wt.%CaO,14-34 wt.% BaO,20-34 wt.%Al_(2)O_(3) and 23-40 wt.%CaO,14-34 wt.%BaO,20-28 wt.% Al_(2)O_(3),respectively.

关键词： Lightweight steel Non-reactive mold flux Molecular dynamics Viscosity Simplex grid method

Wettability between titanium-containing steels and TiN ceramic substrate

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Journal of Iron and Steel Research International 2023年第4期30卷 677-686页

作者： Ya-cen Deng Hao Liu Min Zhang xu-bin Zhang Qiang-qiang Wang Sheng-ping he College of Materials Science and Engineering Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and Advanced MaterialsChongqing UniversityChongqing 400044China Institute of Material Engineering and Technology Pangang Group Research Institute Co.Ltd.Panzhihua 617000SichuanChina

The wettability between TiN ceramic substrates and steels with various Ti contents was studied under an argon atmosphere at 1550℃ using a modified sessile drop *** electron probe microanalyzer and thermodynamic calculations were applied to investigate the interface between the steels and the TiN substrates as well as the surface of solidified steel *** measured apparent contact angles between the TiN substrates and steels were 96°,91°,and 146°,as the Ti content in the steel samples was 0.01,0.31,and 0.68 wt.%,*** reaction products were found at the interface,and only physical interactions *** wettability between high titanium steels(0.68 wt.%Ti)and TiN ceramic substrates should be evaluated from various perspectives,as many TiN particles existing in steel made the apparent contact angle increased significantly,deviating from the true value of contact angle.

关键词： Wettability Contact angle High-Ti steel TiN ceramic

A New Functor from D_5-Mod to E_6-Mod

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Acta Mathematica Sinica,English Series 2016年第8期32卷 867-892页

作者： Xiao ping xu Hua Loo-Keng Key Mathematical Laboratory Institute of MathematicsAcademy of Mathematics & System SciencesChinese Academy of Sciences

We find a new representation of the simple Lie algebra of type E6 on the polynomial algebra in 16 variables, which gives a fractional representation of the corresponding Lie group on 16-dimensional space. Using this representation and Shen＇s idea of mixed product, we construct a new functor from Ds-Mod to E6-Mod. A condition for the functor to map a finite-dimensional irreducible Ds-module to an infinite-dimensional irreducible E6-module is obtained. Our results yield explicit constructions of certain infinite-dimensional irreducible weight E6-modules with finite-dimensional weight subspaces. In our approach, the idea of Kostant＇s characteristic identities plays a key role.

关键词： Simple Lie algebra of type E6 simple Lie algebra of type Ds module category functor,irreducibility