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期刊论文 29

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分布式优化；高性能算法；多智能体系统；机器学习问题；随机梯度 1

刚度 1

变化高阶动态 1

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气雾化 1

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滚珠丝杠进给驱动系统 1

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动态变化滚珠丝杠进给系统的智能非同位控制策略

刘辉, 张俊, 赵万华

《工程（英文）》 2017年 第3卷 第5期   页码 641-647 doi: 10.1016/J.ENG.2017.04.007

摘要：
滚珠丝杠进给驱动系统由于其细长的螺旋主轴和部件之间连接部分的灵活性，具有变化的高阶动态特性，并且当采用直线光栅尺进行直接位置测量时，它还具有非同位控制的明显特征。长期以来，动态特性和非同位状况一直是运动和振动控制困难的根源，它们还会降低轴的运动精度。在本研究中，考虑到灵活性及其变化，我们建立了基于频率的子结构动态模型，并充分研究了动态特性对位置变化的依赖，开发出由模态特征修正器（MCM）和智能自适应调整算法（ATA）组成的控制策略。MCM 由峰值滤波器和陷波滤波器组成，从而将设备动态变为虚拟同位系统，且可以避免控制溢出。使用人工神经网络（ANN）作为平滑参数插值器，可以实时更新滤波器的参数，以便应对进给驱动系统的动态变化。我们已经在实际的进给驱动系统中验证了所提出策略的有效性和鲁棒性。

关键词： 滚珠丝杠进给驱动系统     变化高阶动态     非同位控制     模态特征修正器     智能自适应调整算法    

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Numerical solution, simulation and testing of the thermal dynamic characteristics of ball-screws

XIA Junyong, HU Youmin, WU Bo, SHI Tielin

《机械工程前沿（英文）》 2008年 第3卷 第1期   页码 28-36 doi: 10.1007/s11465-008-0007-4

摘要： This research focuses on the characteristics of how a ball-screw changes its temperature corresponding to the periodic change of the end-most heat source. Based on the theory of heat transfer, this paper supplies a numerical solution to the non-homogeneous equation of heat transfer through the group explicit (GE) finite difference approach. The temperature distribution for the ball-screw at different times and directions is shown. By simulating and modeling the temperature field and thermal deformation of the ball-screw under periodically varying heat sources, this paper describes the thermal dynamic characteristics of the ball-screw under such conditions. By testing the thermal dynamic characteristics of the ball-screw, the numerical solution is validated.

关键词： numerical solution     temperature corresponding     temperature distribution     end-most     ball-screw    

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数控车床丝杠进给系统刚度对定位精度的影响

吴南星,胡如夫,孙庆鸿

《中国工程科学》 2004年 第6卷 第9期   页码 46-49

摘要：

数控车床丝杠进给系统刚度对系统的失动量和定位精度影响较大。基于进给系统质量和弹簧力学模型，给出了进给系统轴向刚度和扭转刚度对失动量的影响与定位误差的解析表达式，为进给系统结构设计、降低系统的失动量和提高系统的定位精度提供了理论依据；结合实例进行了应用分析计算，取得了明显效果。

关键词： 数控机床     刚度     失动量     定位精度    

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Simulation of cottonseed cake melt flow in metering zone of a single screw extruder

Hong HE, Jianguo ZHOU,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 263-269 doi: 10.1007/s11705-009-0276-4

摘要： Research on the extrusion of natural polymers (food, feed, etc.) is relatively new due to the complex physicochemical transformations of raw materials, although plastics melt conveying and transport have been well studied. The structure and composition, rheological behavior as well as extrusion processing of natural polymer are much more complicated. In this study, a quasi-three-dimensional (3D) fluid flow model for non-Newtonian, non-isothermal and undeveloped temperature was developed, the model prediction being in reasonably good agreement with the experiment. Results show that the influence of moisture content, among other process variables, is the most significant, followed by screw speed. Some interaction exists between these two variables and the screw speed effect becomes marginal at high moisture contents. In addition, viscosity change in the channel was studied.

关键词： quasi-three-dimensional     rheological     viscosity     processing     influence    

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characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings by high-energy ball

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

《机械工程前沿（英文）》 2011年 第6卷 第2期   页码 176-181 doi: 10.1007/s11465-011-0220-4

摘要：

High-energy ball milling is an effective method to produce nanocrystalline oxides. In this study, a conventional ZrO2-7%Y2O3spray powder was ball-milled to produce nanocrystalline powders with high levels of crystalline disorders for deposition of thermal barrier coatings. The powder was milled both with 100Cr6 steel balls and with ZrO2-3%Y2O3 ceramic balls as grinding media. The milling time was varied in order to investigate the effect of the milling time on the crystallite size. The powders were investigated in terms of their crystallite sizes and morphologies by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that under given milling conditions the powder was already nanostructured after 40 min milling. The crystallite size decreased significantly with increasing milling time within first 120 min. After that, a further increase of milling time did not lead to a significant reduction of the crystallite size. Ball-milling led to lattice microstrains. Milling with the steel balls resulted in finer nano-sized crystal grains, but caused the contamination of the powder. The nano-sized crystal grains coarsened during the heat-treatment at 1250°C.

关键词： nanostrucured powders     yttria stabilized zirconia (YSZ)     high-energy ball milling     thermal barrier coatings    

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Computer-Aided Design System for CP Single-Screw Compressor

SHEN Jing-feng, YAO Fu-sheng

《机械工程前沿（英文）》 2006年 第1卷 第1期   页码 21-25 doi: 10.1007/s11465-005-0018-3

摘要：

To design various optimum parameters and simulate the working process of CP single-screw compressor, the Computer-Aided Design (CAD) system for the CP single-screw compressor has been established. A new method based on computer graphics technology, database technology, object-oriented programming technology, and visual simulation technology has been adopted in this CAD system. The system has integrated solid modeling function with parameterization design function and animator simulation function based on analyzing the working principle of the CP single-screw compressor. The experimental results show that the CAD system for the CP single-screw compressor is practical and feasible.

关键词： CP single-screw     database technology     simulation technology     programming technology     animator simulation    

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Augmented hydrogen production by gasification of ball milled polyethylene with Ca(OH)

Giovanni Cagnetta, Kunlun Zhang, Qiwu Zhang, Jun Huang, Gang Yu

《环境科学与工程前沿（英文）》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1096-5

摘要：

PE ball milling pretreatment induces higher H2 production and purity by gasification.

Ca(OH)2 reacts at solid state with PE boosting H2 and capturing CO2.

Ca(OH)2 significantly reduces methanation side-reaction.

关键词： Hydrogen production     Gasification     Plastic waste     High energy ball milling    

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Effect of surgical factors on the augmentation of cement-injectable cannulated pedicle screw fixation

Haolin Sun, Chun Liu, Shunlun Chen, Yanjie Bai, Huilin Yang, Chunde Li, Lei Yang

《医学前沿（英文）》 2019年 第13卷 第5期   页码 590-601 doi: 10.1007/s11684-019-0710-z

摘要： Bone cement-augmented pedicle screw system demonstrates great efficacy in spinal disease treatments. However, the intrinsic drawbacks associated with clinically used polymethylmethacrylate (PMMA) cement demands for new bone cement formulations. On the basis of our previous studies, a novel injectable and biodegradable calcium phosphate-based nanocomposite (CPN) for the augmentation of pedicle screw fixation was systematically evaluated for its surgical feasibility and biomechanical performance by simulated and animal osteoporotic bone models, and the results were compared with those of clinical PMMA cement. ASTM-standard solid foam and open-cell foam models and decalcified sheep vertebra models were employed to evaluate the augmentation effects of CPN on bone tissue and on the cement-injected cannulated pedicle screws (CICPs) placed in osteoporotic bone. Surgical factors in CICPs application, such as injection force, tapping technique, screw diameter, and pedicle screw loosening scenarios, were studied in comparison with those in PMMA. When directly injected to the solid foam model, CPN revealed an identical augmentation effect to that of PMMA, as shown by the similar compressive strengths (0.73±0.04 MPa for CPN group vs. 0.79±0.02 MPa for PMMA group). The average injection force of CPN at approximately 40–50 N was higher than that of PMMA at approximately 20 N. Although both values are acceptable to surgeons, CPN revealed a more consistent injection force pattern than did PMMA. The dispersing and anti-pullout ability of CPN were not affected by the surgical factors of tapping technique and screw diameter. The axial pullout strength of CPN evaluated by the decalcified sheep vertebra model revealed a similar augmentation level as that of PMMA (1351.6±324.2 N for CPN vs. 1459.7±304.4 N for PMMA). The promising results of CPN clearly suggest its potential for replacing PMMA in CICPs augmentation application and the benefits of further study and development for clinical uses.

关键词： bone cement     pedicle screw     degenerative spinal diseases     calcium phosphate     injectable    

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Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S. RAO, Bansi D. NAYAK, Lala B. SUKLA, Barada K. MISHRA

《环境科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 281-293 doi: 10.1007/s11783-013-0484-5

摘要： Bioleaching of a low grade chalcopyrite (ball mill spillage material) was tested for copper recovery in shake flasks. The original samples (as received) were thermally activated (600°C, 30 min) to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characterization studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy (FESEM-EDS) and X-ray Fluorescence (XRF) analysis indicated mostly SiO . With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30°C, 150 r·min , 49% copper could be recovered in 30 days from the finest particle size (-1+ 0.75 mm) of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.

关键词： ball mill spillage     thermal activation     bioleaching     copper    

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Explicit optimization method for cutting-screw-thread on the basis of dual-RSM

Zhengbao LEI, Shubin WEI, Qingyun DU

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 423-430 doi: 10.1007/s11465-010-0109-7

摘要： To obtain the explicit function for optimizing the cutting-screw-thread (CST) in crash, the simulations of frontal crash at the speed of 56 km/h have been carried out in VPG. The peak acceleration in crash has been taken as the evaluation index of energy absorption characteristics. First, the single factor experiment was taken based on six parameters affecting on the absorption characteristics of CST. Second, the peak acceleration function of each parameter by using response surface method (RSM) is obtained. Third, the explicit resultant peak acceleration function of six parameters by using RSM again is obtained. A dual RSM-based explicit method is proposed. According to this function, the best size dimensions of CST in different crash conditions could be easily obtained. Finally, an example shows that the values of the calculation errors for simulation value and target value (40 g) are 3.6% and 1.3%, respectively. This method can satisfy the demand for engineering accuracy.

关键词： vehicle engineering     crash     safety     explicit method     response surface method    

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Effect of friction coefficients on the dynamic response of gear systems

BALL, Xuejun LI

《机械工程前沿（英文）》 2017年 第12卷 第3期   页码 397-405 doi: 10.1007/s11465-017-0415-4

摘要：

The inevitable deterioration of the lubrication conditions in a gearbox in service can change the tribological properties of the meshing teeth. In turn, such changes can significantly affect the dynamic responses and running status of gear systems. This paper investigates such an effect by utilizing virtual prototype technology to model and simulate the dynamics of a wind turbine gearbox system. The change in the lubrication conditions is modeled by the changes in the friction coefficients, thereby indicating that poor lubrication causes not only increased frictional losses but also significant changes in the dynamic responses. These results are further demonstrated by the mean and root mean square values calculated by the simulated responses under different friction coefficients. In addition, the spectrum exhibits significant changes in the first, second, and third harmonics of the meshing components. The findings and simulation method of this study provide theoretical bases for the development of accurate diagnostic techniques.

关键词： dynamic response     friction coefficient     wind loads     wind turbine gearbox    

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Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 431-437 doi: 10.1007/s11465-010-0110-1

摘要： The theory and algorithm of the homogeneous transformation matrix (HTM) method are applied in establishing the kinematic error model of five-axis machining tool with two-axis turntable. Based on this model, a new method for the kinematic error separation in five-axis numerical control (NC) machining tool is proposed. In this study, three types of simultaneous three-axis control motions are designed for each rotary axis to identify the deviations. In the measurement, two translational axes and one rotary axis are simultaneously controlled to keep a constant distance between the tool and the worktable. Telescoping double ball bar is used to measure the relative distance between the spindle and the worktable in the motion of NC machining tool. Finally, the value measured by telescoping double ball bar is substituted into the model to obtain kinematic error of NC machining tool. Comparison has confirmed that the proposed method is high precision and can be applied to effectively and conveniently measure the five-axis machining tool.

关键词： error modeling     error separation     telescoping double ball bar     five-axis numerical control (NC) machining tool    

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Erratum to: One-step ball milling-prepared nano Fe

Xingguo Guo, Qiuying Wang, Ting Xu, Kajia Wei, Mengxi Yin, Peng Liang, Xia Huang, Xiaoyuan Zhang

《环境科学与工程前沿（英文）》 2020年 第14卷 第4期 doi: 10.1007/s11783-020-1258-5

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Ball milling promoted direct liquefaction of lignocellulosic biomass in supercritical ethanol

Chunyan Yang, Xiaoliang Yuan, Xueting Wang, Kejing Wu, Yingying Liu, Changjun Liu, Houfang Lu, Bin Liang

《化学科学与工程前沿（英文）》 2020年 第14卷 第4期   页码 605-613 doi: 10.1007/s11705-019-1841-0

摘要： In the present work, ball milling was applied for the pretreatment of lignocellulose to obtain high conversion and bio-oil yield in supercritical ethanol. Ball milling substantially decreased the crystallinity and particle size of lignocellulose, thereby improving its accessibility in ethanol solvent. An increased bio-oil yield of 59.2% was obtained for the ball milled camphorwood sawdust at 300°C, compared with 39.6% for the original lignocellulose. Decreased crystallinity significantly benefited the conversion of the cellulose component from 60.8% to 91.7%, and decreased particle size was beneficial for the conversion of all components. The obtained bio-oil had a high phenolic content, as analyzed by gas chromatography-mass spectrometry. Methoxylation and retro-aldol condensation were observed during alcoholysis, and the reaction pathways of lignocellulose in supercritical ethanol were attributed to the action of free radicals.

关键词： ball milling     lignocellulose     supercritical ethanol     liquefaction     bio-oil    

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A rolling 3-UPU parallel mechanism

Zhihuai MIAO, Yan’an YAO, Xianwen KONG

《机械工程前沿（英文）》 2013年 第8卷 第4期   页码 340-349 doi: 10.1007/s11465-013-0282-6

摘要：

A novel rolling mechanism is proposed based on a 3-UPU parallel mechanism in this paper. The rolling mechanism is composed of two platforms connected by three UPU (universal-prismatic-universal) serial-chain type limbs. The degree-of-freedom of the mechanism is analyzed using screw theory. Gait analysis and stability analysis are presented in detail. Four rolling modes of the mechanism are discussed and simulated. The feasibility of the rolling mechanism is verified by means of a physical prototype. Finally, its terrain adaptability is enhanced through planning the rolling gaits.

关键词： parallel mechanism     rolling mechanism     screw theory    

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标题 作者 时间 类型 操作

动态变化滚珠丝杠进给系统的智能非同位控制策略

刘辉, 张俊, 赵万华

期刊论文

Numerical solution, simulation and testing of the thermal dynamic characteristics of ball-screws

XIA Junyong, HU Youmin, WU Bo, SHI Tielin

期刊论文

数控车床丝杠进给系统刚度对定位精度的影响

吴南星,胡如夫,孙庆鸿

期刊论文

Simulation of cottonseed cake melt flow in metering zone of a single screw extruder

Hong HE, Jianguo ZHOU,

期刊论文

characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings by high-energy ball

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

期刊论文

Computer-Aided Design System for CP Single-Screw Compressor

SHEN Jing-feng, YAO Fu-sheng

期刊论文

Augmented hydrogen production by gasification of ball milled polyethylene with Ca(OH)

Giovanni Cagnetta, Kunlun Zhang, Qiwu Zhang, Jun Huang, Gang Yu

期刊论文

Effect of surgical factors on the augmentation of cement-injectable cannulated pedicle screw fixation

Haolin Sun, Chun Liu, Shunlun Chen, Yanjie Bai, Huilin Yang, Chunde Li, Lei Yang

期刊论文

Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S. RAO, Bansi D. NAYAK, Lala B. SUKLA, Barada K. MISHRA

期刊论文

Explicit optimization method for cutting-screw-thread on the basis of dual-RSM

Zhengbao LEI, Shubin WEI, Qingyun DU

期刊论文

Effect of friction coefficients on the dynamic response of gear systems

BALL, Xuejun LI

期刊论文

Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

期刊论文

Erratum to: One-step ball milling-prepared nano Fe

Xingguo Guo, Qiuying Wang, Ting Xu, Kajia Wei, Mengxi Yin, Peng Liang, Xia Huang, Xiaoyuan Zhang

期刊论文

Ball milling promoted direct liquefaction of lignocellulosic biomass in supercritical ethanol

Chunyan Yang, Xiaoliang Yuan, Xueting Wang, Kejing Wu, Yingying Liu, Changjun Liu, Houfang Lu, Bin Liang

期刊论文

A rolling 3-UPU parallel mechanism

Zhihuai MIAO, Yan’an YAO, Xianwen KONG

期刊论文