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Cross-coupled controller design for triaxial motion systems based on second-order contour error estimation

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Science China(Technological Sciences) 2015年第7期58卷 1209-1217页

作者： zhao huan ZHU LiMin DING Han State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

The cross-coupled control(CCC)is widely applied to reduce contour errors in contour-following *** such situation,the contour error estimation plays an important ***,the linear or second-order estimation approach is adopted for biaxial motion systems,whereas only linear approach is available for triaxial *** this paper,the second-order contour error estimation,which was presented in our previous work,is utilized to determine the variable CCC gains for motion control systems with three *** integrated stable motion control strategy,which combines the feedforward,feedback and CCC controllers,is developed for multiaxis CNC *** results on a triaxial platform indicate that the CCC scheme based on the second-order estimation,compared with that based on the linear one,significantly reduces the contour error even in the conditions of high tracking feedrate and small radius of curvature.

关键词： cross-coupled controller contour error cross-coupled gains triaxial motion system computer numerical control (CNC)

Development of FPGA Based NURBS Interpolator and Motion Controller with Multiprocessor Technique

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 940-947页

作者： zhao huan ZHU Limin XIONG Zhenhua DING Han State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

The high-speed computational performance is gained at the cost of huge hardware resource,which restricts the application of high-accuracy algorithms because of the limited hardware cost in practical *** solve the problem,a novel method for designing the field programmable gate array(FPGA)-based non-uniform rational B-spline(NURBS) interpolator and motion controller,which adopts the embedded multiprocessor technique,is proposed in this *** hardware and software design for the multiprocessor,one of which is for NURBS interpolation and the other for position servo control,is *** analysis and experiments on an X-Y table are carried out,hardware cost as well as consuming time for interpolation and motion control is compared with the existing *** experimental and comparing results indicate that,compared with the existing methods,the proposed method can reduce the hardware cost by 97.5% using higher-accuracy interpolation algorithm within the period of 0.5 ms.A method which ensures the real-time performance and interpolation accuracy,and reduces the hardware cost significantly is proposed,and it’s practical in the use of industrial application.

关键词： NURBS interpolator FPGA-based interpolation multiprocessor system on a programmable chip (SOPC) motion controller

Nia1 and Nia2 are Involved in Exogenous Salicylic Acid-induced Nitric Oxide Generation and Stomatal Closure in Arabidopsis

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Journal of Integrative Plant Biology 2010年第3期52卷 298-307页

作者： Fushun Hao Shiling zhao huan Dong huan Zhang Lirong Sun Chen Miao Henan Key Laboratory of Plant Stress Biology College of Life Science Henan University Kaifeng 475004 China

Phytohormone salicylic acid （SA） plays important roles in plant responses to environmental stress. However, knowledge about the molecular mechanisms for SA affecting the stomatal movements is limited. In this paper, we demonstrated that exogenous SA significantly induced stomatal closure and nitric oxide （NO） generation in Arabidopsis guard cells based on genetic and physiological data. These effects were significantly inhibited by the NO scavenger c-PTIO, NO synthase （NOS） inhibitor L-NAME or nitrate reductase suppressor tungstate respectively, implying that NOS and nitrate reductase （NR） participate in SA-evoked stomatal closing. Furthermore, the effects of SA promotion of stomatal closure and NO synthesis are significantly suppressed in NR single mutants of nial, nia2 or double mutant niallnia2, compared with the wild type plants. This suggests that both Nial and Nia2 are involved in SA-stimulated stomatal closure. In addition, pharmacological experiments showed that protein kinases, cGMP and cADPR are involved in SA-mediated NO accumulation and stomatal closure induced by SA in Arabidopsis.

关键词： no english key word

Formation Applicability Analysis of Stimulated Reservoir Volume Fracturing and Case Analysis

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Petroleum 2021年第2期7卷 160-167页

作者： huan zhao Wei Li Hui Pu Konghang Yang College of Petroleum Engineering Northeast Petroleum UniversityDaqingHeilongjing163318China Department of Petroleum Engineering University of North DakotaGrand ForksND58202USA Tazhong Oil and Gas Development Department Tarim Oilfield CompanyKorla841000China

Stimulated Reservoir Volume(SRV)fracturing is a key technology of unconventional oil and gas exploration and *** gain a deeper understanding of tight sandstone reservoirs and draw on the development experience of hydraulic fracturing,the authors conduct a large number of detailed investigations of geological characteristics in the regions that have implemented SRV *** on the data of rock mechanics parameters,insitu stress characteristics,brittleness characteristics and natural fractures,the influencing factors of SRV fracturing in tight oil reservoirs were *** results show that the SRV fracturing is suitable for geological reservoirs with the characteristics of medium to high elastic modulus,low to medium Poisson’s ratio,low stress difference,medium to high brittleness and naturally fractured reservoirs,where natural fractures have a significant *** A,a tight sandstone region,has moderate elastic modulus,low Poisson’s ratio,low ground stress difference and medium brittleness,and has the feasibility of volume *** field case of the Y325 well shows that SRV fracturing technology has obvious effect on increasing *** technology is applicable to the Region A.

关键词： Tight sandstone reservoir Shale reservoir Geological characteristics SRV fracturing

Force tracking impedance control with unknown environment via an iterative learning algorithm

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Science China(Information Sciences) 2019年第5期62卷 47-49页

作者： Xiuquan LIANG huan zhao Xiangfei LI Han DING State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology

Dear editor,Force tracking control is important for constrained operations. In recent years, impedance control is garnering increasing attention in robot force control. A new two-phase impedance function through null stiffness in an original impedance equation to satisfy zero-force tracking error for any environment was presented in [1, 2]. Further improvement was performed in [3]. However, the hy-

关键词： Force tracking impedance control with unknown environment via an iterative learning algorithm

A Selective Attention Guided Initiative Semantic Cognition Algorithm for Service Robot

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International Journal of Automation and computing 2018年第5期15卷 559-569页

作者： huan-zhao Chen Guo-Hui Tian Guo-Liang Liu School of Control Science and Engineering University of Shandong

With the development of artificial intelligence and robotics, the study on service robot has made a significant progress in recent years. Service robot is required to perceive users and environment in unstructured domestic environment. Based on the perception,service robot should be capable of understanding the situation and discover service task. So robot can assist humans for home service or health care more accurately and with initiative. Human can focus on the salient things from the mass observation information. Humans are capable of utilizing semantic knowledge to make some plans based on their understanding of the environment. Through intelligent space platform, we are trying to apply this process to service robot. A selective attention guided initiatively semantic cognition algorithm in intelligent space is proposed in this paper. It is specifically designed to provide robots with the cognition needed for performing service tasks. At first, an attention selection model is built based on saliency computing and key area. The area which is highly relevant to service task could be located and referred as focus of attention（FOA）. Second, a recognition algorithm for FOA is proposed based on a neural network. Some common objects and user behavior are recognized in this step. At last, a unified semantic knowledge base and corresponding reasoning engine is proposed using recognition result. Related experiments in a real life scenario demonstrated that our approach is able to mimic the recognition process in humans, make robots understand the environment and discover service task based on its own cognition. In this way, service robots can act smarter and achieve better service efficiency in their daily work.

关键词： Service robot cognition computing selective attention semantic knowledge base artificial neural network.

Fracture Mechanism of the Formation with a Natural Flaw Under a Single-Tooth Cutting

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Acta Mechanica Solida Sinica 2020年第5期33卷 719-730页

作者： Siqi Li Wei Li Tie Yan Fuqing Bi huan zhao Xin Ling Institute of Petroleum Engineering Northeast Petroleum UniversityDaqing163318HeilongjiangChina The Fifth Oil Production Plant of Daqing Oilfield Daqing163513HeilongjiangChina

The process of a single-tooth cutting formation is taken as the representative to analyze the fracture mechanism of the formation with natural flaws under the PDC drill *** modeling of the stress field distribution of the formation under a single tooth is proposed ***,the modeling of the stress intensity factor K,T-stress and the initiation angleθof the flaw under two far-field compressive loads in two cases are presented based on the mode-II ***,the results of theoretical calculations and simulations are given and *** on the analysis undertaken,it can be concluded that the confinement ratioλapplying on the flaw changes nonlinearly with the variation inα+φ.The relationship between the dimensionless ratioβx/βy of T-stress and the rotational polar angleφis a parabola with an upward *** the direction of the cutting force is consistent with the flaw,the stress intensity factor K and the initiation angleθat the tip of the flaw reach the *** addition,the angle between the cutting force and the flaw weakens the T-stress and inhibits the crack initiation and propagation of the *** results of numerical simulations show good agreement with theoretical calculations.

关键词： Single-tooth cutting Stress field Stress intensity factor Initiation angle Extended finite element

The residual oil distribution regularity of low permeability oilfield

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Petroleum 2015年第2期1卷 112-117页

作者： huan zhao Hongjun Yin Key Laboratory for Enhanced Oil Recovery of Ministry of Education Northeast Petroleum UniversityHeilongjiangDaqing 163318China

Study on the residual oil distribution regularity is the important thing during the middle and later stage of the *** understanding and development of oilfield,the research methods of remaining oil are *** block A is a low permeability oilfield and complex relationship between injection wells and production *** well pattern has low control of sand *** on the characteristics and the geological and dynamic data,technology of integrated 3-D geological modeling with reservoir numerical simulation is ensured to study the residual ***,deposition facies and flowing units are studied to analyze the residual oil distribution *** a result,the types of residual oil were confirmed and the basis for the following development adjustment of the well block is provided.

关键词： Residual oil Low permeability oilfield 3-D geological modeling Reservoir numerical simulation

17.13% Efficiency and Superior Thermal Stability of Organic Solar Cells Based on a Comb-Shape Active Blend

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Energy & Environmental Materials 2023年第6期6卷 266-272页

作者： Zhipeng Yin Qingjie Wang huan zhao Haiqiao Wang Ning Li Weijie Song School of Materials Science and Engineering NingboTech UniversityNingbo 315100China Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSchool of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640China

With rapid progress,organic solar cells(OSCs)are getting closer to the target of real ***,the stability issue is still one of the biggest challenges that have to be ***,the thermal stability of OSCs is far from meeting the requirements of the ***,based on the layer-by-layer(LBL)process and by utilizing the dissolubility nature of solvent and materials,binary inverted OSCs(ITO/AZO/PM6/BTP-eC9/MoO3/Ag)with comb shape active morphology are *** efficiency of 17.13%and simultaneous superior thermal stability(with 93%of initial efficiency retained in~9:00 h under 85℃in N_(2))are demonstrated,showing superior stability to reference *** enhancements are attributed to the formed optimal comb shape of the active layer,which could provide a larger D/A interface,thus more charge carriers,render the active blend a more stable morphology,and protect the electrode by impeding ion's migration and *** the best of our knowledge,this is the best thermal stability of binary OSCs reported in the literature,especially when considering the high efficiency of over 17%.

关键词： comb-shape blend high efficiency organic solar cell thermal stability