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Accurate Measurement Method for Tube's Endpoints Based on Machine Vision

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Chinese Journal of Mechanical Engineering 2017年第1期30卷 152-163页

作者： LIU shaoli JIN Peng LIU Jianhua WANG Xiao SUN Peng School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Tubes are used widely in aerospace vehicles, and their accurate assembly can directly affect the assembling reliability and the quality of products. It is important to measure the processed tube＇s endpoints and then fix any geometric errors correspondingly. However, the traditional tube inspection method is time-consuming and complex operations. Therefore, a new measurement method for a tube＇s endpoints based on machine vision is proposed. First, reflected light on tube＇s surface can be removed by using photometric linearization. Then, based on the optimization model for the tube＇s endpoint measurements and the principle of stereo matching, the global coordinates and the relative distance of the tube＇s endpoint are obtained. To confirm the feasibility, ll tubes are processed to remove the reflected light and then the endpoint＇s positions of tubes are measured. The experiment results show that the measurement repeatability accuracy is 0.167 mm, and the absolute accuracy is 0.328 ram. The measurement takes less than 1 min. The proposed method based on machine vision can measure the tube＇s endpoints without any surface treatment or any tools and can realize on line measurement.

关键词： machine vision non-contact measurement reflection light tube endpoint measurement

Methanogenesis acceleration of fresh landfilled waste by micro-aeration

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Journal of Environmental Sciences 2005年第3期17卷 371-374页

作者： shaoli-ming HEPin-jing ZHANGHua YUXiao-hua LIGuo-jian StateKeyLaboratoryofPollutionControlandReclamation TongjiUniversityShanghai20092China

When municipal solid waste(MSW) with high content of food waste is landfilled, the rapid hydrolysis of food waste results in the imbalance of anaerobic metabolism in the landfill layer, indicated by accumulation of volatile fatty acids(VFA) and decrease of pH value. This occurrence could lead to long lag time before the initiation of methanogenesis and to the production of strong leachate. Simulated landfill columns with forced aeration, with natural ventilation, and with no aeration, were monitored regarding their organics degradation rate with leachate recirculation. Hydrolysis reactions produced strong leachate in the column with no aeration. With forced aeration, the produced VFA could be effectively degraded, leading to the reduction in COD of the leachate effluent since the week 3. The CH_4 in the landfill gas from the column with aeration rate of 0.39 m3/(m3·d) and frequency of twice/d, leachate recirculation rate of 12.2 mm/d and frequency of twice/d, could amount to 40%(v/v) after only 20 weeks. This amount had increased up to 50% afterward even with no aeration. Most of COD in the recirculated leachate was removed. Using natural ventilation, CH_4 could also be produced and the COD of the leachate effluent be reduced after 10 weeks of operation. However, the persistent existence of oxygen in the landfill layer yielded instability in methanogenesis process.

关键词： MSW landfill methanogenesis leachate recirculation forced aeration natural ventilation

Dynamical analysis of tumor-immune-help T cells system

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International Journal of Biomathematics 2019年第7期12卷 51-70页

作者： Huixia Li shaoli Wang Fei Xu School of Mathematics and Statistics Henan University Kaifeng 475001HenanP.R.China School of Mathematics and Statistics Bioinformatics Center Henan UniversityKaifeng 475001HenanP.R.China Department of Mathematics Wilfrid Laurier University WaterlooOntarioN2L 3C5Canada

In this paper,we construct a mathematical model to investigate the interaction between the tumor cells,the immune cells and the helper T cells(HTCs).We perform math-ematical analysis to reveal the stability of the equilibria of the *** our model,the HTCs are stimulated by the identification of the presence of tumor *** investigation implies that the presence of tumor antigens may inhibit the existence of high steady state of tumor cells,which leads to the elimination of the bistable behavior of the tumor-immune system,*** equilibrium corresponding to the high steady state of tumor cells is *** immune intensity c as bifurcation parameter,there exists saddle-node ***,there exists a critical value C*,at which a Hopf bifurcation *** stability and direction of Hopf bifurcation are discussed.

关键词： Tumor-immune-helper T cells system inhibit high steady state saddle-node bifurcation Hopf bifurcation

Reaction mechanism and chemoselectivity of gold(Ⅰ)-catalyzed cycloaddition of 1-(1-alkynyl) cyclopropyl ketones with nucleophiles to yield substituted furans

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Science China Chemistry 2012年第7期55卷 1413-1420页

作者： YAN YunFeng FANG Ran GENG ZhiYuan WANG YongCheng LIU shaoli Gansu Key Laboratory of Polymer Materials College of Chemistry and Chemical EngineeringNorthwest Normal UniversityGansu 730070China College of Chemistry and Chemical Engineering Lanzhou University Gansu 730000China

The mechanisms of gold（I）-catalyzed cycloaddition of 1-（1-alkynyl） cyclopropyl ketones with nucleophiles have been investi- gated using density functional theory calculations at the B3LYP/6-31G （d, p） level of theory. A polarizable continuum model （PCM） has been established in order to evaluate the effects of solvents on the reactions. The results of the calculations indicate that the first step of the catalytic cycle is the cyclization of the carbonyl oxygen onto the triple bond which forms a new and stable resonance structure of an oxonium ion and a carbocation intermediate. The subsequent ring expansion step results in the formation of the final product and regeneration of the catalyst. Furthermore, the regioselectivity and effect of substituents has been discussed, including an analysis of energy, bond length, and natural bond orbital （NBO） charge distributions in the rate-determining step. Our computational results are consistent with earlier experimental observations.

关键词： substituted furans Au(l)-catalyzed regioselectivity substituent effects

A Design of Nonlinear Scaling and Nonlinear Optimal Motion Cueing Algorithm for Pilot’s Station

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Wuhan University Journal of Natural Sciences 2021年第6期26卷 513-520页

作者： ZHU Daoyang YAN Jun DUAN shaoli College of Intelligent Manufacturing Wuhan Technical College of CommunicationsWuhan 430065HubeiChina

Motion cueing algorithms(MCA)are often applied in the motion *** this paper,a nonlinear optimal MCA,taking into account translational and rotational motions of a simulator within its physical limitation,is designed for the motion platform aiming to minimize human’s perception error in order to provide a high degree of ***,the movement sensation center of most MCA is placed at the center of the upper platform,which may cause a certain ***’s station should be paid full attention to in the *** from this,the scaling and limiting module plays an important role in optimizing the motion platform workspace and reducing false cues during motion *** should be used along within the washout filter to decrease the amplitude of the translational and rotational motion signals uniformly across all frequencies through the MCA.A nonlinear scaling method is designed to accurately duplicate motions with high realistic behavior and use the platform more efficiently without violating its physical *** simulation experiment is verified in the longitudinal/pitch direction for motion *** result implies that the proposed method can not only overcome the problem of the workspace limitations in the simulator motion reproduction and improve the realism of movement sensation,but also reduce the false cues to improve dynamic fidelity during the motion simulation process.

关键词： nonlinear optimal motion cueing algorithm(MCA) nonlinear scaling and limiting pilot’s station dynamic fidelity

Development of Cueing Algorithm Based on “Closed-Loop” Control for Flight Simulator Motion System

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Wuhan University Journal of Natural Sciences 2019年第5期24卷 376-382页

作者： ZHU Daoyang DUAN shaoli FANG Da College of Intelligent Manufacturing Wuhan Technical College of Communications

The classical washout algorithm had fixed gains and manually constructed filters, so that it led to poor adaptability. Furthermore, it lost the sustained acceleration cues of high-and mid-frequency in cross-over(tilt-coordination) channel, and the acceleration of cross-over frequency was also limited by angular velocity limiter, so the false cues in flight simulation process were clearly perceived by pilots. The paper studied the characteristics of the classical washout algorithm and flight simulator motion platform, tried to redesign the source of cross-over acceleration channel and translation acceleration channel, and transferred the part of cross-over acceleration that was unsimulated sustained acceleration to translation acceleration channel. Comparisons were mainly made between classical washout algorithm and revised algorithm in a longitudinal/pitch direction. The evaluation was based on the implementation of human vestibular perception system. The results demonstrated that the revised algorithm could significantly reduce the phase lag, and improved the spikes tracking performance. Furthermore, sensory angular velocity and the error of sensory acceleration were strictly controlled within the threshold of human perception system, and the displacement was a little broader than the classical washout algorithm. Therefore, it was proved that the new algorithm could diminish the filters parameters and heighten the self-adaptability for the washout algorithm. In addition, the magnitude of false cues was remarkably reduced during flight simulator, and the workspace utilization of the motion platform was developed by "closed-loop" control system.

关键词： classical washout algorithm human vestibular system "closed-loop" control false cues

Influence of Rare Earth on Property of Low Chromium Semi-Steel

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Journal of Iron and Steel Research International 2003年第3期10卷 50-53页

作者： LIUJian-hua XIEDan-yang LIChang-sheng shaoli ZHANGRui-jun YanshanUniversity Qinhuangdao066004China JiangsuUniversity Zhenjiang212013China HebeiNormalCollege Shijiazhuang050012China

The influence of rare earth( RE) content on mechanical properties and abrasion resistance of low chromium semi-steel was studied by means of metallographic examination,scanning electron microscopic examination and mechanical property test. The experiment results show that RE can improve the comprehensive properties,especially in combination with proper heat treatment. The optimum properties of low chromium semi-steel modified by RE of 0. 25 % could be obtained by normalization at 950 ℃ for 3 h. The main reason is the change in morphology and distribution of eutectic carbide and the precipitation of granular carbides.

关键词： rare earth low chromium semi-steel eutectic carbide precipitation granular carbide

Design, Synthesis and Application of a Robust d_(3)-Methyithiolating Reagent

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Chinese Journal of Chemistry 2023年第22期41卷 3045-3049,I0002页

作者： Yanyang Zhang Yishuo Ren Jian Zhang shaoli Liu Yahui Li Key Laboratory of Agri-Food Safety of Anhui Province School of Resources and EnvironmentAnhui Agricultural UniversityHefeiAnhui230036China Key Laboratory of Green Pesticide and Agricultural Bio-engineering Ministry of EducationGuizhou UniversityGuiyangGuizhou 550025China Collegeof Chemistry and Chemical Engineering YantaiUniversityYantaiShandong 264005China

A deuterated methylthiolating reagent with a broad spectrum,designated as DMTp,has been ingeniously *** new reagent can be produced with high efficiency through the simple combination of commercially available methyl 3-thiopropanoate and CD_(3)*** novel SCD_(3) reagent exhibits excellent reactivity with electrophiles such as alkyl iodides,benzyl chlorides,aryl halides(l,Br)and aryl triflates,resulting in high levels of deuterium content(99%D).Representative deuterated methylthiolated biomolecules,such as Sulfoxaflor,havebeen synthesizedforuse in pharmaceutical discoveryand development.

关键词： New reagent d_(3)-Methylthiolating reagent Metal-catalyzed Application Aryl halides C1 building blocks Cleavage reactions Organohalides

Tribological evaluation of thermoplastic polyurethane-based bearing materials under water lubrication:Effect of load,sliding speed,and temperature

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Friction 2024年第8期12卷 1801-1815页

作者： shaoli JIANG Janet SSWONG Debashis PUHAN Tian YUAN Xiuqin BAI Chengqing YUAN State Key Laboratory of Maritime Technology and Safety Wuhan University of TechnologyWuhan 430063China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Yusuf Hamied Department of Chemistry University of CambridgeLensfield RoadCambridge CB21EWUK

Polymers are widely used in bearing *** the case of water-lubricated stern tube bearings,thermoplastic polyurethane(TPU)-based composites are used due to their excellent wear resistance,corrosion resistance,and tunable mechanical *** tribological performance,however,depends on operating *** this work,TPU was blended with carbon fiber,graphene platelet,and ultra-high molecular weight polyethylene(UHMWPE).Friction tests of TPU based-composites against copper countersurface were carried out in water to mimic the actual operating conditions of the *** of the resulting contacts were in the boundary lubrication regime,in which friction was attributed to both contact mechanics of asperities as well as water *** results show that the viscoelasticity of TPU has a considerable impact on its tribological *** lubrication at 50°C promotes the softening of polymer surface material during sliding,resulting in higher fluctuation in the coefficient of friction and wear *** is attributed to the reduced thermomechanical *** addition,Schallamach waviness is observed on worn *** tribological properties of TPU are significantly improved by the inclusion of carbon fiber,graphene platelet,and *** formation of graphene transfer-layers and UHMWPE transfer film reduces friction and wear loss,while the inclusion of carbon fiber enhances wear resistance due to improved mechanical properties and load bearing capacity.

关键词： friction thermoplastic polyurethane(TPU) water-lubricated bearings graphene platelet carbon fibers ultra-high molecular weight polyethylene(UHMWPE)